The authors would like to thank R&#252;diger Rosenkranz and Sven Niese (Fraunhofer IKTS-MD) for their assistance in sample preparation, and Ude Hangen, Douglas Stauffer, Ryan Major and Oden Warren (Hysitron Inc.) for their technical support on the PI95 TEM holder. The support of the Center for Advancing Electronics Dresden (cfaed) and the Dresden Center for Nanoanalysis (DCN) at Technische Universit&#228;t Dresden is acknowledged as well.

1. Preparazione del campione per la Focused Ion Beam (FIB) assottigliamento (Figura 1) <ol><li> Cleave l&#39;intero wafer in piccoli chip (circa 10 mm x 10 mm) con uno scriba diamante. </li><li> Segnare le posizioni della struttura &quot;da punta a punta&quot; sui chip. </li><li> Visto il chip con una macchina a dadi per ottenere barre di 60 micron per 2 dimensioni mm. Il bar comprende la struttura &quot;punta-punta&quot; al centro. </li><li> Incollare la barra bersaglio su un mezzo anello Cu utilizzando la colla super. Avanti, incollare la barra su un palco campione Cu anche utilizzando la colla super. Quindi, l&#39;uso d&#39;argento pasta per impostare la conduzione tra il mezzo anello e la fase di campionamento di rame. Nota: Quando si maneggia il campione, assicurarsi di indossare sempre un braccialetto antistatico per evitare scariche elettrostatiche, che possono danneggiare la struttura sensibile nel campione. </li></ol> 2. FIB assottigliamento nel microscopio elettronico a scansione (Figura 2) <ol><li> Mettere il campione ottenuto nel passaggio 1 su unn SEM fase del campione e inserire il palco con cautela nel SEM. </li><li> Scegliere la modalità di deposizione, e impostare le dimensioni (area e spessore) dello strato di protezione Pt necessario. Utilizzare sempre un fascio di ioni 30 kV per mantenere la massima precisione. Tune la corrente per ottenere l&#39;efficienza soddisfatto, dipendente dalle dimensioni del livello Pt necessario. <ol><li> Depositare una linea Pt a contattare uno pad allo stadio Cu (potenziale di terra). Successivamente, depositare uno spesso strato di Pt in cima alla struttura &quot;punta-punta&quot;, che è molto importante per ridurre al minimo il danno litio durante il processo di assottigliamento FIB e rafforzare il sottile lamelle. Si tratta di una procedura standard utilizzata in preparazione FIB. </li><li> Fare attenzione a non introdurre percorsi conduttivi tra i due pad sulla parte superiore della struttura &quot;da punta a punta&quot;, attraverso lo strato di Pt quando si esegue la deposizione Pt. Qualsiasi percorso conduttivo si corto circuito elettrico (Figura 2A e B). </li></ol></li><li> FIB fresatura <ol><li> Utilizzare una tensione di 30 kV e corrente di 10 pA per il taglio finale. Thin barra di destinazione in un TEM lamella H-bar con uno spessore compreso tra 150 e 180 nm. </li><li> Tagliare una tacca vicino al pad (V + pad), che sarà toccato da una punta del trasduttore nel TEM. Utilizzare la tacca come un indicatore per identificare il pad corretta nel TEM. </li></ol></li></ol> 3. Il campione di trasferimento dal SEM al TEM <ol><li> Indossare il braccialetto antistatico prima di toccare il campione. </li><li> Smontare il campione H-bar preparata dal palco SEM. Mantenere il campione sul palco Cu durante la rimozione dal SEM. </li><li> Fissare la fase Cu sul supporto TEM. Spostare la punta del trasduttore del titolare TEM vicino alla struttura di test (alcune centinaia di micrometri distanza dalla struttura di test) al microscopio ottico. <ol><li> Inserire il supporto TEM nel TEM attenzione. Non utilizzare alcun trattamento di pulizia (es pulizia plasma) durante il trprocesso ansfer, altrimenti le lamelle può essere influenzato. </li></ol></li><li> Mantenere il tempo per il trasferimento del campione entro 15 minuti o più breve per evitare troppa esposizione all&#39;umidità ambientale e ossigeno. </li></ol> 4. Stabilire il collegamento elettrico (Figura 3) <ol><li> Collegare il titolare TEM al sistema di controllo e il SourceMeter. Poi accendere il sistema di controllo e il SourceMeter. </li><li> Monitorare la punta del trasduttore nel TEM quando si fa l&#39;approccio grossolano della punta del trasduttore alla struttura di prova sintonizzando le manopole sul supporto TEM. <ol><li> Spostare la punta del trasduttore del titolare TEM vicino al pad V + (≤ 500 nm). Portare la punta del trasduttore allo stesso livello (Z: altezza) come pad. Tune la posizione della punta e rendere la punta rivolto verso il centro della V + pad. </li></ol></li><li> Contattare la punta del trasduttore al pad V +. Impostare una bassissima tensione sulla punta (0,5 V a circa 1 V) mentre si avvicina il pad. Monitorare il simultaneo di correnteusly per assicurarsi che si stabilisce il contatto. </li></ol> 5. In Situ TDDB Experiment <ol><li> Utilizzare una tensione di 200 kV di accelerato nel TEM. Spostare il fascio di elettroni per l&#39;area di interesse; scegliere un ingrandimento adeguato e fuoco l&#39;immagine. </li><li> Utilizzare bassa illuminazione passaggi (≤ 8) per ridurre i danni del fascio sulla struttura di prova. Utilizzare una apertura del condensatore di localizzare la zona di illuminazione solo all&#39;interno della parte sottile del campione H-bar. </li><li> Applicare una tensione costante (≤ 40 V) sulla struttura &quot;da punta a punta&quot; con il SourceMeter durante la registrazione delle immagini TEM in situ (2-3 fotogrammi / sec). Registrare automaticamente le immagini utilizzando un codice di autoregolamentazione script, ad esempio, utilizzando il software DigitalMicrograph. </li><li> Pausa l&#39;esperimento vedendo una diffusione apparente di metallo nei dielettrici Ulk e fare il Electron Spectroscopic Imaging (ESI) analisi chimica. <ol><li> Inserire l&#39;apertura del filtro a fessura nel Omegun filtro di energia nel TEM. </li><li> Tune la larghezza dell&#39;apertura filtro limo per ottenere una larghezza di energia adeguata (10-20 eV) nello spettro degli elettroni perdita di energia (EELS). </li><li> Spostare l&#39;energia per il picco di assorbimento di rame M-edge nei EELS. </li><li> Torna alla modalità di imaging per acquisire un&#39;immagine TEM energia filtrata alla M-edge picco di assorbimento Cu. </li><li> Spostare l&#39;energia per la pre-bordo del M-bordo di rame e ricevere un&#39;altra immagine TEM energia filtrata. </li><li> Correggere la deriva del campione tra le due immagini. </li><li> Dividete la prima immagine dalla seconda per ottenere l&#39;immagine rapporto tra salto di Cu. </li></ol></li><li> Continua l&#39;esperimento TDDB: riapplicare una tensione costante (≤ 40 V) sulla struttura &quot;da punta a punta&quot; con il SourceMeter e registrare le immagini TEM. </li></ol> 6. Tomografia Computerizzata <ol><li> Eseguire TEM tomografia computerizzata quando l&#39;esperimento TDDB è finito, per ottenere informazioni sulla distribuzione 3D sulla diparticelle ffused. </li><li> Inclinare il campione e registrare una serie di inclinazione di 138 °. Utilizzare un passo inclinazione di 1 °, e registrare l&#39;immagine in ogni fase in modalità STEM in campo chiaro (BF). </li><li> Ricostruire la serie (include allineamento immagini, determinando asse di ribaltamento, ricostruendo volume e segmentazione per formare il volume tomografica 3D). </li></ol>

<ol>
	<li>Edelstein, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Full+Copper+Wiring+in+a+Sub-0.25+&#181;m+CMOS+ULSI+Technology.">Full Copper Wiring in a Sub-0.25 &#181;m CMOS ULSI Technology.</a> IEDM Tech. Dig. , 773-776 (1997).</li><li>List, S., Bamal, M., Stucchi, M., Maex, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+global+view+of+interconnects.">A global view of interconnects.</a> Microelectron. Eng. 83 (11/12), 2200-2207 (2006).</li><li>Meindl, J. D., Davis, J. A., Zarkesh-Ha, P., Patel, C. S., Martin, K. P., Kohl, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interconnect+opportunities+for+gigascale+integration.">Interconnect opportunities for gigascale integration.</a> IBM J. Res. Develop. 46 (2/3), 245-263 (2002).</li><li>Zhang, X. F., Wang, Y. W., Im, J. H., Ho, P. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chip-Package+Interaction+and+Reliability+Improvement+by+Structure+Optimization+for+Ultralow-k+Interconnects+in+Flip-Chip+Packages.">Chip-Package Interaction and Reliability Improvement by Structure Optimization for Ultralow-k Interconnects in Flip-Chip Packages.</a> IEEE Trans. Device Mater. Reliab. 12 (2), 462-469 (2012).</li><li>Lee, K. D., Ogawa, E. T., Yoon, S., Lu, X., Ho, P. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electromigration+reliability+of+dual-damascene+Cu/porous+methylsilsesquioxane+low+k+interconnects.">Electromigration reliability of dual-damascene Cu/porous methylsilsesquioxane low k interconnects.</a> Appl. Phys. Lett. 82 (13), 2032 (2003).</li><li>Zschech, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stress-induced+phenomena+in+nanosized+copper+interconnect+structures+studied+by+x-ray+and+electron+microscopy.">Stress-induced phenomena in nanosized copper interconnect structures studied by x-ray and electron microscopy.</a> J. Appl. Phys. 106 (9), 093711 (2009).</li><li>Tan, T. L., Hwang, N., Gan, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dielectric+Breakdown+Failure+Mechanisms+in+Cu-SiOC+low-k+interconnect+system.">Dielectric Breakdown Failure Mechanisms in Cu-SiOC low-k interconnect system.</a> IEEE Trans. Bimodal. 7 (2), 373-378 (2007).</li><li>Zhao, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+observation+of+the+1/E+dependence+of+time+dependent+dielectric+breakdown+in+the+presence+of+copper.">Direct observation of the 1/E dependence of time dependent dielectric breakdown in the presence of copper.</a> Appl. Phys. Lett. 98 (3), 032107 (2011).</li><li>Breuer, T., Kerst, U., Boit, C., Langer, E., Ruelke, H., Fissel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conduction+and+material+transport+phenomena+of+degradation+in+electrically+stressed+ultra-low-k+dielectric+before+breakdown.">Conduction and material transport phenomena of degradation in electrically stressed ultra-low-k dielectric before breakdown.</a> J. Appl. Phys. 112 (12), 124103 (2012).</li><li>Lloyd, J. R., Liniger, E., Shaw, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simple+model+for+time-dependent+dielectric+breakdown+in+inter-+and+intralevel+low-k+dielectrics.">Simple model for time-dependent dielectric breakdown in inter- and intralevel low-k dielectrics.</a> J. Appl. Phys. 98 (8), 084109 (2005).</li><li>Chen, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Comprehensive+Study+of+Low-k+SiCOH+TDDB+Phenomena+and+Its+Reliability+Lifetime+Model+Development.">A Comprehensive Study of Low-k SiCOH TDDB Phenomena and Its Reliability Lifetime Model Development.</a> , 46-53 (2006).</li><li>Wu, W., Duan, X., Yuan, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modeling+of+Time-Dependent+Dielectric+Breakdown+in+Copper+Metallization).">Modeling of Time-Dependent Dielectric Breakdown in Copper Metallization).</a> IEEE Trans. Device Mater. Reliab. 3 (2), 26-30 (2003).</li><li>Achanta, R. S., Plawsky, J. L., Gill, W. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+time+dependent+dielectric+breakdown+model+for+field+accelerated+low-k+breakdown+due+to+copper+ions.">A time dependent dielectric breakdown model for field accelerated low-k breakdown due to copper ions.</a> Appl. Phys. Lett. 91 (23), 234106 (2007).</li><li>Chen, F., Shinosky, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Soft+breakdown+characteristics+of+ultralow-k+time-dependent+dielectric+breakdown+for+advanced+complementary+metal-oxide+semiconductor+technologies.">Soft breakdown characteristics of ultralow-k time-dependent dielectric breakdown for advanced complementary metal-oxide semiconductor technologies.</a> J. Appl. Phys. 108 (5), 054107 (2010).</li><li>Yeap, K. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+Experimental+Methodology+for+the+In-Situ+Observation+of+the+Time-Dependent+Dielectric+Breakdown+Mechanism+in+Copper/Low-k+On-Chip+Interconnect+Structures.">An Experimental Methodology for the In-Situ Observation of the Time-Dependent Dielectric Breakdown Mechanism in Copper/Low-k On-Chip Interconnect Structures.</a> , (2013).</li><li>Yeap, K. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+study+on+low-k+interconnect+time-dependent-dielectric-breakdown+mechanisms).">In situ study on low-k interconnect time-dependent-dielectric-breakdown mechanisms).</a> J. Appl. Phys. 115 (12), 124101 (2014).</li><li>Liao, Z. Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In-situ+Study+of+the+TDDB-Induced+Damage+Mechanism+in+Cu/Ultra-low-k+Interconnect+Structures.">In-situ Study of the TDDB-Induced Damage Mechanism in Cu/Ultra-low-k Interconnect Structures.</a> Microelectron. Eng. In Press, (2014).</li><li>Liao, Z. Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+New+In+Situ+Microscopy+Approach+to+Study+the+Degradation+and+Failure+Mechanisms+of+Time-Dependent+Dielectric+Breakdown:+Set-Up+and+Opportunities.">A New In Situ Microscopy Approach to Study the Degradation and Failure Mechanisms of Time-Dependent Dielectric Breakdown: Set-Up and Opportunities.</a> Adv. Eng. Mater. 16 (5), 486-493 (2014).</li><li>Lee, Z., Meyer, J. C., Rose, H., Kaiser, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimum+HRTEM+image+contrast+at+20+kV+and+80+kV-Exemplified+by+graphene.">Optimum HRTEM image contrast at 20 kV and 80 kV-Exemplified by graphene.</a> Ultramicroscopy. 112 (1), 39-46 (2012).</li><li>Bell, D. C., Russo, C. J., Kolmykov, D. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=40+keV+atomic+resolution+TEM.">40 keV atomic resolution TEM.</a> Ultramicroscopy. 114, 31-37 (2012).</li><li>Kaiser, U., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transmission+electron+microscopy+at+20+kV+for+imaging+and+spectroscopy.">Transmission electron microscopy at 20 kV for imaging and spectroscopy.</a> Ultramicroscopy. 111 (8), 1239-1246 (2011).</li><li>Egerton, R. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Control+of+radiation+damage+in+the+TEM.">Control of radiation damage in the TEM.</a> Ultramicroscopy. 127, 100-108 (2013).</li><li>Jiang, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Damage+mechanisms+in+electron+microscopy+of+insulating+materials.">Damage mechanisms in electron microscopy of insulating materials.</a> J. Phys. D: Appl. Phys. 46, 305502 (2013).</li><li>Buban, J. P., Ramasse, Q., Gipson, B., Browning, N. D., Stahlberg, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-resolution+low-dose+scanning+transmission+electron+microscopy.">High-resolution low-dose scanning transmission electron microscopy.</a> J. Electron Microsc. 59 (2), 103-112 (2010).</li><li>Egerton, R. F., Li, P., Malac, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Radiation+damage+in+the+TEM+and+SEM.">Radiation damage in the TEM and SEM.</a> Micron. 35 (6), 399-409 (2004).</li></ol>

No competing financial interests.

Il prerequisito del successo nell&#39;esperimento TDDB è buona preparazione del campione, in particolare nel processo di fresatura FIB nel SEM. In primo luogo, uno spesso strato di Pt in cima alla struttura &quot;punta-punta&quot; deve essere depositato. Lo spessore e la dimensione dello strato Pt può essere regolata dall&#39;operatore SEM, ma devono seguire tre principi: (1) lo spessore e la dimensione sono sufficienti a proteggere la zona di destinazione da possibili danni fascio di ioni durante l&#39;intero process...

Poiché interconnessioni Cu sono stati dapprima introdotti nella tecnologia di integrazione ultra-larga scala (ULSI) nel 1997 1, low-k e ultra-low-k (Ulk) dielettrici sono stati adottati nel back-end-of-line (beol) come i materiali isolanti tra interconnessioni su chip. La combinazione di nuovi materiali, ad esempio, Cu per minore resistenza e basso-k dielettrici / Ulk per minori capacità, supera gli effetti di aumento della resistenza-capacità (RC) ritardo causato dalla interconnessione dimensionale restringimento 2, 3. Tuttavia, questo beneficio è stato invaso dalla scala aggressiva continuo di dispositivi microelettronici negli ultimi anni. L&#39;uso di basso k / Ulk materiali comporta varie sfide nel processo di fabbricazione e di affidabilità del prodotto, in particolare se il campo di interconnessione raggiunge circa 100 nm o meno 4-6. TDDB riferisce al meccanismo di rottura fisica di un materiale dielettrico in funzione del temposotto un campo elettrico. Il test di affidabilità TDDB viene solitamente eseguita in condizioni accelerate (campo elettrico elevato e / o temperatura elevata). La TDDB in on-chip stacks interconnessione è uno dei meccanismi di guasto più critici per i dispositivi microelettronici, che ha già sollevato preoccupazioni intensi nella comunità affidabilità. Si continuerà ad essere al centro dell&#39;attenzione degli ingegneri di affidabilità da dielettrici Ulk con ancora più deboli proprietà elettriche e meccaniche vengono integrati nei dispositivi di nodi tecnologici avanzati. Esperimenti dedicati sono stati condotti per indagare il meccanismo di rottura TDDB 7-9, ed una notevole quantità di sforzo è stato investito per sviluppare modelli che descrivono la relazione tra campo elettrico e la durata dei dispositivi 10-13. Gli studi esistenti beneficio della comunità degli ingegneri di affidabilità in microelettronica; tuttavia, molti Challenesistono ancora GES e molte domande ancora devono essere risolte in dettaglio. Ad esempio, i modelli collaudati per descrivere il meccanismo di fallimento e di degradazione cinetica fisici nel processo TDDB e la rispettiva verifica sperimentale sono ancora carenti. Di particolare esigenza, è necessario un modello più opportuno sostituire la √E modello conservatore 14. Come una parte molto importante delle indagini TDDB, analisi tipico fallimento si trova ad affrontare una sfida senza precedenti, cioè, fornire la prova completa e difficile da spiegare la fisica del meccanismi di guasto e di cinetica di degradazione. A quanto pare, il controllo di milioni di vias e metri di scala nanometrica linee Cu uno per uno ed ex situ esponendo il sito fallimento non è la scelta appropriata di ostacolo a questa sfida, perché richiede molto tempo, e solo informazioni limitate sui cinetica del meccanismo di danno può essere fornito. Pertanto, un compito urgente è emersa per sviluppare unnd per ottimizzare gli esperimenti e per ottenere una procedura migliore per studiare i meccanismi di rottura TDDB e cinetica di degradazione. In questo lavoro, dimostreremo in situ metodologia sperimentale per indagare il meccanismo di fallimento TDDB in Cu / Ulk stack di interconnessione. Un TEM con la capacità di immagini di alta qualità e dell&#39;analisi chimica viene utilizzata per studiare il processo cinetica in strutture di test dedicati. Il test elettrico in situ è integrato nella esperimento TEM per fornire un campo elettrico elevato al dielettrici. Una struttura su misura &quot;da punta a punta&quot;, costituita da interconnessioni Cu completamente incapsulato e isolato da un materiale ULK, è stato progettato nel nodo tecnologia CMOS a 32 nm. La procedura sperimentale qui descritto può essere esteso anche ad altre strutture di dispositivi attivi.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Automatic Dicing Saw</td>
			<td>DISCO Kiru-Kezuru-Migaku Technologies</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Scanning Electron Microscope</td>
			<td>Zeiss</td>
			<td>Zeiss Nvision 40</td>
			<td></td>
		</tr>
		<tr>
			<td>Picoindentor</td>
			<td>Hysitron</td>
			<td>Hysitron Pi95</td>
			<td></td>
		</tr>
		<tr>
			<td>Keithley SourceMeter</td>
			<td>Keithley</td>
			<td>Keithley 2602/237</td>
			<td></td>
		</tr>
		<tr>
			<td>Transmission Electron Microscope</td>
			<td>FEI</td>
			<td>FEI Tecnai F20</td>
			<td></td>
		</tr>
		<tr>
			<td>Transmission Electron Microscope</td>
			<td>Zeiss</td>
			<td>Zeiss Libra 200</td>
			<td></td>
		</tr>
	</tbody>
</table>

in situ time-dependent dielectric breakdown in the transmission electron microscope: a possibility to understand the failure mechanism in microelectronic devices

The time-dependent dielectric breakdown (TDDB) in on-chip interconnect stacks is one of the most critical failure mechanisms for microelectronic devices. The aggressive scaling of feature sizes, both on devices and interconnects, leads to serious challenges to ensure the required product reliability. Standard reliability tests and post-mortem failure analysis provide only limited information about the physics of failure mechanisms and degradation kinetics. Therefore it is necessary to develop new experimental approaches and procedures to study the TDDB failure mechanisms and degradation kinetics in particular. In this paper, an in situ experimental methodology in the transmission electron microscope (TEM) is demonstrated to investigate the TDDB degradation and failure mechanisms in Cu/ULK interconnect stacks. High quality imaging and chemical analysis are used to study the kinetic process. The in situ electrical test is integrated into the TEM to provide an elevated electrical field to the dielectrics. Electron tomography is utilized to characterize the directed Cu diffusion in the insulating dielectrics. This experimental procedure opens a possibility to study the failure mechanism in interconnect stacks of microelectronic products, and it could also be extended to other structures in active devices.

La figura 4 mostra in campo chiaro (BF) immagini TEM da una prova in situ. Ci sono parzialmente violato TaN / Ta barriere e gli atomi di Cu preesistenti nei dielettrici Ulk prima del test elettrico (Figura 4A) a causa di rimessaggio prolungato in ambiente. Dopo soli 376 sec a 40 V, la ripartizione dielettrica iniziato ed era accompagnata da due principali vie di migrazione di rame dal metallo M1, avente un potenziale positivo con riferimento al lato terra 15-16. Le p...

Watch this Scientific Journal Video about In Situ Time-dependent Dielectric Breakdown in the Transmission Electron Microscope: A Possibility to Understand the Failure Mechanism in Microelectronic Devi

In Situ Time-dependent Dielectric Breakdown in the Transmission Electron Microscope: A Possibility to Understand the Failure Mechanism in Microelectronic Devices

The time-dependent dielectric breakdown (TDDB) in on-chip interconnect stacks is one of the most critical failure mechanisms for microelectronic devices. This paper demonstrates the procedure of an in situ TDDB experiment in the transmission electron microscope, which opens a possibility to study the failure mechanism in microelectronic products.

In Situ in funzione del tempo di rottura dielettrico nel Transmission Electron Microscope: A Con possibilità di capire il meccanismo Fallimento in dispositivi microelettronici

The time-dependent dielectric breakdown (TDDB) in on-chip interconnect stacks is one of the most critical failure mechanisms for microelectronic devices. ...

in-situ-time-dependent-dielectric-breakdown-transmission-electron

Research

JoVE Journal

Engineering

In Situ Time-dependent Dielectric Breakdown in the Transmission Electron Microscope: A Possibility to Understand the Failure Mechanism in Microelectronic Devices

8.6K Views.  Fraunhofer Institute for Ceramic Technologies and Systems. The time-dependent dielectric breakdown (TDDB) in on-chip interconnect stacks is one of the most critical failure mechanisms for microelectronic devices. This paper demonstrates the procedure of an in situ TDDB experiment in the transmission electron microscope, which opens a possibility to study the failure mechanism in microelectronic products. 

Video: In Situ Time-dependent Dielectric Breakdown in the Transmission Electron Microscope: A Possibility to Understand the Failure Mechanism in Microelectronic Devices

Revealing Dynamic Processes of Materials in Liquids Using Liquid Cell Transmission Electron Microscopy

The recent development for in situ transmission electron microscopy, which allows imaging through liquids with high spatial resolution, has attracted significant interests across the research fields of materials science, physics, chemistry and biology. The key enabling technology is a liquid cell. We fabricate liquid cells with thin viewing windows through a sequential microfabrication process, including silicon nitride membrane deposition, photolithographic patterning, wafer etching, cell bonding, etc. A liquid cell with the dimensions of a regular TEM grid can fit in any standard TEM sample holder. About 100 nanoliters reaction solution is loaded into the reservoirs and about 30 picoliters liquid is drawn into the viewing windows by capillary force. Subsequently, the cell is sealed and loaded into a microscope for in situ imaging. Inside the TEM, the electron beam goes through the thin liquid layer sandwiched between two silicon nitride membranes. Dynamic processes of nanoparticles in liquids, such as nucleation and growth of nanocrystals, diffusion and assembly of nanoparticles, etc., have been imaged in real time with sub-nanometer resolution. We have also applied this method to other research areas, e.g., imaging proteins in water. Liquid cell TEM is poised to play a major role in revealing dynamic processes of materials in their working environments. It may also bring high impact in the study of biological processes in their native environment.

We have developed a self-contained liquid cell, which allows imaging through liquids using a transmission electron microscope. Dynamic processes of nanoparticles in liquids can be revealed in real time with sub-nanometer resolution.

Rivelare processi dinamici dei materiali in liquidi con liquido di trasmissione microscopia elettronica cellulare

The recent development for in situ transmission electron microscopy, which allows imaging through liquids with high spatial resolution, has attracted ...

Ricerca

Ingegneria

Detection and Recovery of Palladium, Gold and Cobalt Metals from the Urban Mine Using Novel Sensors/Adsorbents Designated with Nanoscale Wagon-wheel-shaped Pores

Developing low-cost, efficient processes for recovering and recycling palladium, gold and cobalt metals from urban mine remains a significant challenge in industrialized countries. Here, the development of optical mesosensors/adsorbents (MSAs) for efficient recognition and selective recovery of Pd(II), Au(III), and Co(II) from urban mine was achieved. A simple, general method for preparing MSAs based on using high-order mesoporous monolithic scaffolds was described. Hierarchical cubic Ia3d wagon-wheel-shaped MSAs were fabricated by anchoring chelating agents (colorants) into three-dimensional pores and micrometric particle surfaces of the mesoporous monolithic scaffolds. Findings show, for the first time, evidence of controlled optical recognition of Pd(II), Au(III), and Co(II) ions and a highly selective system for recovery of Pd(II) ions (up to ~95%) in ores and industrial wastes. Furthermore, the controlled assessment processes described herein involve evaluation of intrinsic properties (e.g., visual signal change, long-term stability, adsorption efficiency, extraordinary sensitivity, selectivity, and reusability); thus, expensive, sophisticated instruments are not required. Results show evidence that MSAs will attract worldwide attention as a promising technological means of recovering and recycling palladium, gold and cobalt metals.

Because of the importance and extensive use of palladium, gold and cobalt metals in high-technology equipment, their recovery and recycling constitute an important industrial challenge. The metal recovery system described herein is a simple, low-cost means for the effective detection, removal, and recovery of these metals from the urban mine.

Rilevamento e recupero di palladio, oro e metalli di cobalto dalla miniera urbana Utilizzando novelli Sensori / Adsorbenti designate con nanoscala Wagon a forma di ruote pori

Developing low-cost, efficient processes for recovering and recycling palladium, gold and cobalt metals from urban mine remains a significant challenge in ...

Using Synchrotron Radiation Microtomography to Investigate Multi-scale Three-dimensional Microelectronic Packages

Synchrotron radiation micro-tomography (SR&#181;T) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data acquisition times with high spatial resolution. In the electronics industry there is serious interest in performing failure analysis on 3D microelectronic packages, many which contain multiple levels of high-density interconnections. Often in tomography there is a trade-off between image resolution and the volume of a sample that can be imaged. This inverse relationship limits the usefulness of conventional computed tomography (CT) systems since a microelectronic package is often large in cross sectional area 100-3,600 mm2, but has important features on the micron scale. The micro-tomography beamline at the Advanced Light Source (ALS), in Berkeley, CA USA, has a setup which is adaptable and can be tailored to a sample&#39;s properties, i.e., density, thickness, etc., with a maximum allowable cross-section of 36 x 36 mm. This setup also has the option of being either monochromatic in the energy range ~7-43 keV or operating with maximum flux in white light mode using a polychromatic beam. Presented here are details of the experimental steps taken to image an entire 16 x 16 mm system within a package, in order to obtain 3D images of the system with a spatial resolution of 8.7 &#181;m all within a scan time of less than 3 min. Also shown are results from packages scanned in different orientations and a sectioned package for higher resolution imaging. In contrast a conventional CT system would take hours to record data with potentially poorer resolution. Indeed, the ratio of field-of-view to throughput time is much higher when using the synchrotron radiation tomography setup. The description below of the experimental setup can be implemented and adapted for use with many other multi-materials.

For this study synchrotron radiation micro-tomography, a non-destructive three-dimensional imaging technique, is employed to investigate an entire microelectronic package with a cross-sectional area of 16 x 16 mm. Due to the synchrotron&#39;s high flux and brightness the sample was imaged in just 3 min&#160;with an 8.7 &#181;m spatial resolution.

L&#39;utilizzo delle radiazioni al sincrotrone microtomografia a indagare multi-scala Pacchetti microelettronici tridimensionali

Synchrotron radiation micro-tomography (SR&#181;T) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data ...

Comprehensive Characterization of Extended Defects in Semiconductor Materials by a Scanning Electron Microscope

Extended defects such as dislocations and grain boundaries have a strong influence on the performance of microelectronic devices and on other applications of semiconductor materials. However, it is still under debate how the defect structure determines the band structure, and therefore, the recombination behavior of electron-hole pairs responsible for the optical and electrical properties of the extended defects. The present paper is a survey of procedures for the spatially resolved investigation of structural and of physical properties of extended defects in semiconductor materials with a scanning electron microscope (SEM). Representative examples are given for crystalline silicon. The luminescence behavior of extended defects can be investigated by cathodoluminescence (CL) measurements. They are particularly valuable because spectrally and spatially resolved information can be obtained simultaneously. For silicon, with an indirect electronic band structure, CL measurements should be carried out at low temperatures down to 5 K due to the low fraction of radiative recombination processes in comparison to non-radiative transitions at room temperature. For the study of the electrical properties of extended defects, the electron beam induced current (EBIC) technique can be applied. The EBIC image reflects the local distribution of defects due to the increased charge-carrier recombination in their vicinity. The procedure for EBIC investigations is described for measurements at room temperature and at low temperatures. Internal strain fields arising from extended defects can be determined quantitatively by cross-correlation electron backscatter diffraction (ccEBSD). This method is challenging because of the necessary preparation of the sample surface and because of the quality of the diffraction patterns which are recorded during the mapping of the sample. The spatial resolution of the three experimental techniques is compared.

The optical, electrical, and structural properties of dislocations and of grain boundaries in semiconductor materials can be determined by experiments performed in a scanning electron microscope. Electron microscopy has been used to investigate cathodoluminescence, electron beam induced current, and diffraction of backscattered electrons.

Caratterizzazione completa dei difetti estesi in materiali semiconduttori da un microscopio elettronico a scansione

Extended defects such as dislocations and grain boundaries have a strong influence on the performance of microelectronic devices and on other applications ...

Optical Trap Loading of Dielectric Microparticles In Air

We demonstrate a method to trap a selected dielectric microparticle in air using radiation pressure from a single-beam gradient optical trap. Randomly scattered dielectric microparticles adhered to a glass substrate are momentarily detached using ultrasonic vibrations generated by a piezoelectric transducer (PZT). Then, the optical beam focused on a selected particle lifts it up to the optical trap while the vibrationally excited microparticles fall back to the substrate. A particle may be trapped at the nominal focus of the trapping beam or at a position above the focus (referred to here as the levitation position) where gravity provides the restoring force. After the measurement, the trapped particle can be placed at a desired position on the substrate in a controlled manner. 
In this protocol, an experimental procedure for selective optical trap loading in air is outlined. First, the experimental setup is briefly introduced. Second, the design and fabrication of a PZT holder and a sample enclosure are illustrated in detail. The optical trap loading of a selected microparticle is then demonstrated with step-by-step instructions including sample preparation, launching into the trap, and use of electrostatic force to excite particle motion in the trap and measure charge. Finally, we present recorded particle trajectories of Brownian and ballistic motions of a trapped microparticle in air. These trajectories can be used to measure stiffness or to verify optical alignment through time domain and frequency domain analysis. Selective trap loading enables optical tweezers to track a particle and its changes over repeated trap loadings in a reversible manner, thereby enabling studies of particle-surface interaction.

A protocol for launching and stably trapping selected dielectric microparticles in air is presented.

Optical Trappola Caricamento di dielettrico microparticelle in aria

We demonstrate a method to trap a selected dielectric microparticle in air using radiation pressure from a single-beam gradient optical trap. Randomly ...

A Method for Obtaining Serial Ultrathin Sections of Microorganisms in Transmission Electron Microscopy

Observing cells and cell components in three dimensions at high magnification in transmission electron microscopy requires preparing serial ultrathin sections of the specimen. Although preparing serial ultrathin sections is considered to be very difficult, it is rather easy if the proper method is used. In this paper, we show a step-by-step procedure for safely obtaining serial ultrathin sections of microorganisms. The key points of this method are: 1) to use the large part of the specimen and adjust the specimen surface and knife edge so that they are parallel to each other; 2) to cut serial sections in groups and avoid difficulty in separating sections using a pair of hair strands when retrieving a group of serial sections onto the slit grids; 3) to use a 'Section-holding loop' and avoid mixing up the order of the section groups; 4) to use a 'Water-surface-raising loop' and make sure the sections are positioned on the apex of the water and that they touch the grid first, in order to place them in the desired position on the grids; 5) to use the support film on an aluminum rack and make it easier to recover the sections on the grids and to avoid wrinkling of the support film; and 6) to use a staining tube and avoid accidentally breaking the support films with tweezers. This new method enables obtaining serial ultrathin sections without difficulty. The method makes it possible to analyze cell structures of microorganisms at high resolution in 3D, which cannot be achieved by using the automatic tape-collecting ultramicrotome method and serial block-face or focused ion beam scanning electron microscopy.

This study presents reliable and easy procedures for obtaining serial ultrathin sections of a microorganism without expensive equipment in transmission electron microscopy.

Un metodo per ottenere il seriale sezioni ultrasottili di microrganismi in microscopia elettronica a trasmissione

Observing cells and cell components in three dimensions at high magnification in transmission electron microscopy requires preparing serial ultrathin ...

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

We demonstrate the use of two nuclear-based analytical methods that can follow the modifications of microstructural arrangement of iron-based metallic glasses (MGs). Despite their amorphous nature, the identification of hyperfine interactions unveils faint structural modifications. For this purpose, we have employed two techniques that utilize nuclear resonance among nuclear levels of a stable 57Fe isotope, namely M&#246;ssbauer spectrometry and nuclear forward scattering (NFS) of synchrotron radiation. The effects of heat treatment upon (Fe2.85Co1)77Mo8Cu1B14 MG are discussed using the results of ex situ and in situ experiments, respectively. As both methods are sensitive to hyperfine interactions, information on structural arrangement as well as on magnetic microstructure is readily available. M&#246;ssbauer spectrometry performed ex situ describes how the structural arrangement and magnetic microstructure appears at room temperature after the annealing under certain conditions (temperature, time), and thus this technique inspects steady states. On the other hand, NFS data are recorded in situ during dynamically changing temperature and NFS examines transient states. The use of both techniques provides complementary information. In general, they can be applied to any suitable system in which it is important to know its steady state but also transient states.

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Here, we present a protocol to describe ex situ and in situ investigations of structural transformations in metallic glasses. We employed nuclear-based analytical methods which inspect hyperfine interactions. We demonstrate the applicability of M&#246;ssbauer spectrometry and nuclear forward scattering of synchrotron radiation during temperature-driven experiments.

Metodi di Ex Situ ed In Situ indagini sulle trasformazioni strutturali: il caso di cristallizzazione dei vetri metallici

We demonstrate the use of two nuclear-based analytical methods that can follow the modifications of microstructural arrangement of iron-based metallic ...

Single-Digit Nanometer Electron-Beam Lithography with an Aberration-Corrected Scanning Transmission Electron Microscope

We demonstrate extension of electron-beam lithography using conventional resists and pattern transfer processes to single-digit nanometer dimensions by employing an aberration-corrected scanning transmission electron microscope as the exposure tool. Here, we present results of single-digit nanometer patterning of two widely used electron-beam resists: poly (methyl methacrylate) and hydrogen silsesquioxane. The method achieves sub-5 nanometer features in poly (methyl methacrylate) and sub-10 nanometer resolution in hydrogen silsesquioxane. High-fidelity transfer of these patterns into target materials of choice can be performed using metal lift-off, plasma etch, and resist infiltration with organometallics.

We use an aberration-corrected scanning transmission electron microscope to define single-digit nanometer patterns in two widely-used electron-beam resists: poly (methyl methacrylate) and hydrogen silsesquioxane. Resist patterns can be replicated in target materials of choice with single-digit nanometer fidelity using liftoff, plasma etching, and resist infiltration by organometallics.

Cifra nanometri Litografia di fascio di elettroni con un microscopio elettronico di aberrazione-corretta scansione trasmissione

We demonstrate extension of electron-beam lithography using conventional resists and pattern transfer processes to single-digit nanometer dimensions by ...

Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites

In this work, an easy, low-cost, and widely applicable method was developed to improve the compatibility between the ceramic fillers and the polymer matrix by adding 3-aminopropyltriethoxysilane (KH550) as a coupling agent during the fabrication process of BaTiO3-P(VDF-CTFE) nanocomposites through solution casting. Results show that the use of KH550 can modify the surface of ceramic nanofillers; therefore, good wettability on the ceramic-polymer interface was achieved, and the enhanced energy storage performances were obtained by a suitable amount of the coupling agent. This method can be used to prepare flexible composites, which is highly desirable for the production of high-performance film capacitors. If an excessive amount of coupling agent is used in the process, the non-attached coupling agent can participate in complex reactions, which leads to a decrease in dielectric constant and an increase in dielectric loss.

Here, we demonstrate a simple and low-cost solution-casting process to improve the compatibility between the filler and the matrix of polymer-based nanocomposites using surface modified BaTiO3 fillers, which can effectively enhance the energy density of the composites.

Applicazione di un agente di accoppiamento per migliorare le proprietà dielettriche dei nanocompositi basati su polimeri

In this work, an easy, low-cost, and widely applicable method was developed to improve the compatibility between the ceramic fillers and the polymer ...

In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx

Resistive switching crossbar architecture is highly desired in the field of digital memories due to low cost and high-density benefits. Different materials show variability in resistive switching properties due to the intrinsic nature of the material used, leading to discrepancies in the field because of underlying operation mechanisms. This highlights a need for a reliable technique to understand mechanisms using nanostructural observations. This protocol explains a detailed process and methodology of in&#160;situ nanostructural analysis as a result of electrical biasing using transmission electron microscopy (TEM). It provides visual and reliable evidence of underlying nanostructural changes in real time memory operations. Also included is the methodology of fabrication and electrical characterizations for asymmetric crossbar structures incorporating amorphous vanadium oxide. The protocol explained here for vanadium oxide films can be easily extended to any other materials in a metal-dielectric-metal sandwiched structure. Resistive switching crossbars are predicted to serve the programmable logic and neuromorphic circuits for next-generation memory devices, given the understanding of the operation mechanisms. This protocol reveals the switching mechanism in a reliable, timely, and cost-effective way in any type of resistive switching materials, and thereby predicts the device&#39;s applicability.

In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx

Presented here is a protocol for analyzing nanostructural changes during in&#160;situ biasing with transmission electron microscopy (TEM) for a stacked metal-insulator-metal structure. It has significant applications in resistive switching crossbars for the next generation of programmable logic circuits and neuromimicking hardware, to reveal their underlying operation mechanisms and practical applicability.

Microscopia elettronica a trasmissione in situ con distorsione e fabbricazione di traverse asimmetriche basate su a -VO x afasemista