This work was supported as part of the Advanced Materials for Energy-Water Systems (AMEWS) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences. We gratefully acknowledge helpful discussions with Mark Stoykovich and Paul Nealey.

1. Fabrication of the transfer tool and drain chamber system
<ol>
	<li>Attached (Supplementary Files 1, 2) is the engineering drawing for the drain chamber assembly consisting of two parts: top and bottom. Model this device according to the specifications of the desired system (e.g., the outer diameter of the receiving substrate) and export as an STL file for 3D printing.</li>
	<li>For the top part, utilize a filament printer of choice and print in the lowest resolution possible, inclu...

<ol>
	<li>Shah, A., Torres, P., Tscharner, R., Wyrsch, N., Keppner, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photovoltaic+technology:+the+case+for+thin-film+solar+cells.">Photovoltaic technology: the case for thin-film solar cells.</a> Science. 285 (5428), 692-698 (1999).</li><li>Kim, T. H., 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-colour+quantum+dot+displays+fabricated+by+transfer+printing.">Full-colour quantum dot displays fabricated by transfer printing.</a> Nat. Photon. 5 (3), 176 (2011).</li><li>Nomura, K., 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=Room-temperature+fabrication+of+transparent+flexible+thin-film+transistors+using+amorphous+oxide+semiconductors.">Room-temperature fabrication of transparent flexible thin-film transistors using amorphous oxide semiconductors.</a> Nature. 432 (7016), 488 (2004).</li><li>Pirkle, A., 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=The+effect+of+chemical+residues+on+the+physical+and+electrical+properties+of+chemical+vapor+deposited+graphene+transferred+to+SiO2.">The effect of chemical residues on the physical and electrical properties of chemical vapor deposited graphene transferred to SiO2.</a> Applied Physics Letters. 99 (12), 122108-122110 (2011).</li><li>Chae, S. J., 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=Synthesis+of+large-area+graphene+layers+on+poly-nickel+substrate+by+chemical+vapor+deposition:+wrinkle+formation.">Synthesis of large-area graphene layers on poly-nickel substrate by chemical vapor deposition: wrinkle formation.</a> Advanced Materials. 21 (22), 2328-2333 (2009).</li><li>Zhu, W., 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=Structure+and+electronic+transport+in+graphene+wrinkles.">Structure and electronic transport in graphene wrinkles.</a> Nano Letters. 12 (7), 3431-3436 (2012).</li><li>Paronyan, T. M., Pigos, E. M., Chen, G., Harutyunyan, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formation+of+ripples+in+graphene+as+a+result+of+interfacial+instabilities.">Formation of ripples in graphene as a result of interfacial instabilities.</a> ACS Nano. 5 (12), 9619-9627 (2011).</li><li>Stadermann, M., 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=Fabrication+of+large-area+free-standing+ultrathin+polymer+films.">Fabrication of large-area free-standing ultrathin polymer films.</a> Journal of Visualized Experiments : JoVE. (100), e52832 (2015).</li><li>Zhou, C., 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=Fabrication+of+Nanoporous+Alumina+Ultrafiltration+Membrane+with+Tunable+Pore+Size+Using+Block+Copolymer+Templates.">Fabrication of Nanoporous Alumina Ultrafiltration Membrane with Tunable Pore Size Using Block Copolymer Templates.</a> Advanced Functional Materials. 27 (34), 1701756 (2017).</li><li>Meitl, M. A., 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=Transfer+printing+by+kinetic+control+of+adhesion+to+an+elastomeric+stamp.">Transfer printing by kinetic control of adhesion to an elastomeric stamp.</a> Nature Materials. 5 (1), 33 (2006).</li><li>Suk, J. W., 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=Transfer+of+CVD-grown+monolayer+graphene+onto+arbitrary+substrates.">Transfer of CVD-grown monolayer graphene onto arbitrary substrates.</a> ACS Nano. 5 (9), 6916-6924 (2011).</li><li>Chen, Y., Gong, X. L., Gai, J. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Progress+and+Challenges+in+Transfer+of+Large-Area+Graphene+Films.">Progress and Challenges in Transfer of Large-Area Graphene Films.</a> Advanced Science. 3 (8), 1500343 (2016).</li></ol>

The authors have nothing to disclose.

While many of the steps listed in this protocol are crucial for the success of the thin film transfer, the nature of the custom-designed 3D printed drain chamber allows for broad flexibility, according to the user's specific requirements. For example, if the receiver substrate has a larger diameter than the 25-mm-diameter AAO discs utilized in this study, the drain chamber can be appropriately modified to fit the new specifications. However, there are certain aspects of the protocol that are necessary to ensure effective...

Thin film and nanomembrane-based devices have recently garnered wide interest due to their potential use in a broad range of applications, ranging from flexible photovoltaics and photonics, foldable displays, and wearable electronics1,2,3. A requirement for the fabrication of these various types of devices is the transfer of thin films to the surfaces of arbitrary substrates, which remains challenging due to the fragility of these films and the frequent production of macroscale defect structures, such as wrinkles, cracks, and tears, within the films after transfer4,5,6,7. Manual transfer by hand, tweezers, and wire loops are common methods of thin film transfer, but inevitably result in structural incongruities and plastic deformation8,9. Various types of thin film transfer methodologies have been explored such as: 1) polydimethylsiloxane (PDMS) stamp transfer, which involves the use of an elastomeric stamp to obtain the thin film from the donor substrate and subsequently transfer to the receiving substrate10, and 2) sacrificial layer transfer11, in which an etchant is used to selectively dissolve a sacrificial layer between the support substrate and the thin film, thereby lifting off the thin film. However, these techniques alone do not necessarily allow for thin film transfer without incurring damage to or defect formation within the thin films12.
Here, we present a novel, low-cost, and generalizable facile method based on sacrificial layer lift-off and meniscus-guided transfer within a custom-designed, 3D-printed drain chamber system, to mechanically place block copolymer (BCP) thin films onto the centers of porous substrates such as anodized aluminum oxide (AAO) discs with little-to-no incurred macroscale defect structures, such as wrinkles, tears, and cracks. In the present context, these transferred thin films can then be used as devices in water filtration studies, potentially after sequential infiltration synthesis (SIS) processing9. Image analysis of transferred films obtained from optical microscopy show that the meniscus-guided, drain-chamber system provides smooth, robust, and wrinkle-free samples. In addition, the images also demonstrate the system&#39;s ability to reliably place the thin film membranes onto the centers of the receiving substrates. Our results have significant implications for any type of device application requiring the transfer of thin film structures onto the surfaces of arbitrary porous substrates.

<table border="0" cellpadding="0" cellspacing="0" style="width:631px;" width="631">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:264px;">35% sodium polyacrylic acid solution</td>
			<td style="width:73px;">Sigma Aldrich</td>
			<td style="width:123px;">9003-01-4&#160;&#160;</td>
			<td style="width:171px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Amicon Stirred Cell model 8010 10mL</td>
			<td style="width:73px;">Millipore</td>
			<td style="width:123px;">5121</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:264px;">Anodized aluminum oxide, 0.2u thickness, 25mm diameter</td>
			<td style="width:73px;">Sigma Aldrich</td>
			<td style="width:123px;">WHA68096022</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">o ring neoprene 117</td>
			<td style="width:73px;">Grainger</td>
			<td>1BUV7</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Objet500 Connex3 3D Printer</td>
			<td style="width:73px;">Stratasys</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Onshape 3D software</td>
			<td style="width:73px;">onshape</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Polylactic acid filament</td>
			<td style="width:73px;">Ultimaker</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">ultimaker3 3d filament printer</td>
			<td style="width:73px;">Ultimaker</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:264px;">Vero Family printable materials</td>
			<td style="width:73px;">Stratasys</td>
			<td style="width:123px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

procedure for the transfer of polymer films onto porous substrates with minimized defects

The fabrication of devices containing thin film composite membranes necessitates the transfer of these films onto the surfaces of arbitrary support substrates. Accomplishing this transfer in a highly controlled, mechanized, and reproducible manner can eliminate the creation of macroscale defect structures (e.g., tears, cracks, and wrinkles) within the thin film that compromise device performance and the usable area per sample. Here, we describe a general protocol for the highly controlled and mechanized transfer of a polymeric thin film onto an arbitrary porous support substrate for eventual use as a water filtration membrane device. Specifically, we fabricate a block copolymer (BCP) thin film on top of a sacrificial, water-soluble poly(acrylic acid) (PAA) layer and silicon wafer substrate. We then utilize a custom-designed, 3D-printed transfer tool and drain chamber system to deposit, lift-off, and transfer the BCP thin film onto the center of a porous anodized aluminum oxide (AAO) support disc. The transferred BCP thin film is shown to be consistently placed onto the center of the support surface due to the guidance of the meniscus formed between the water and the 3D-printed plastic drain chamber. We also compare our mechanized transfer-processed thin films to those that have been transferred by hand with the use of tweezers. Optical inspection and image analysis of the transferred thin films from the mechanized process confirm that little-to-no macroscale inhomogeneities or plastic deformations are produced, as compared to the multitude of tears and wrinkles produced from manual transfer by hand. Our results suggest that the proposed strategy for thin film transfer can reduce defects when compared to other methods across many systems and applications.

The BCP membrane samples were fabricated according to the previously described procedure9. The samples were placed onto the lip of the loading arm of the 3D-printed transfer tool (Figure 1, left) and subsequently lowered, with a laboratory jack, onto the entrance ramp of the 3D-printed drain chamber tool (Figure 1, right). A sacrificial layer of poly(acrylic acid) (PAA) between the BCP membrane and underly...

Watch this Scientific Journal Video about Procedure for the Transfer of Polymer Films Onto Porous Substrates with Minimized Defects at JoVE.com

Procedure for the Transfer of Polymer Films Onto Porous Substrates with Minimized Defects

We present a procedure for highly controlled and wrinkle-free transfer of block copolymer thin films onto porous support substrates using a 3D-printed drain chamber. The drain chamber design is of general relevance to all procedures involving transfer of macromolecular films onto porous substrates, which is normally done by hand in an irreproducible fashion.

The fabrication of devices containing thin film composite membranes necessitates the transfer of these films onto the surfaces of arbitrary support ...

To study polymer thin films in membrane applications, materials must be transferred from a polished, smooth substrate to porous substrates in a fashion that does not fold, wrinkle, tear, or plastically deform the film. This video describes a 3D printable drain chamber designed to achieve this aim and concerns steps four through six in the process flow shown here. Samples used in this work consist of silicon wafer substrates into which are spin coated a stack of water soluble polyacrylic acid followed by a random copolymer mat and a polystyrene block polymethyl methacrylate block copolymer.The aim of steps four through six is to transfer this pore-forming block copolymer from the silicon wafer onto a porous anodized aluminum oxide membrane to enable subsequent transformation into a functional filtration device. The drain chamber consists of a top ramp that enables the introduction of the polymer film stack and a bottom portion which holds the porous substrate and deionized water. The top part is printed from PLA from a filament printer, and the bottom portion was printed from an inkjet 3D printer.A sample transfer tool is also printed from PLA using the filament printer. The first part attaches to a laboratory jack so the sample can be raised and lowered smoothly and without vibrations from hand movements. The second part holds the BCP wafer piece in place.With that, the transfer process can begin. First, the BCP tool is assembled. The clamp portion is threaded so a screw can secure it to the lab jack.The anodized aluminum oxide substrate is then placed inside of the bottom portion of the drain chamber using forceps. Next, a rubber O-ring is inserted to ensure a waterproof seal. The ramp portion of the drain chamber is screwed on tightly.Last, clear vinyl tubing is attached to the spout at the bottom portion of the drain chamber and the other end to the syringe which is inside of a syringe pump to be able to control the drainage rate. Next, the silicon wafer with the polymer stack is placed on the transfer tool, and the drain chamber is also filled with deionized water. The silicon wafer is then lowered slowly into the water, which causes the polyacrylic acid layer to begin to dissolve.This dissolution delaminates the polymer film from the silicon wafer leaving it to float on the water surface. The transfer tool is next removed, and the draining is activated by starting the syringe pump. The water is suctioned through the aluminum oxide substrate and out of the chamber by the pump.Shown here is the draining taking place at a rate of one milliliter per minute. The angle of the ramp and design of the chamber directs the polymer film towards the center of the cylinder. Here, the membrane and the water level have reached the cylindrical body of the device, creating a more prominent meniscus, which holds the membrane taut and centered as it is lower to the underlying, anodized aluminum oxide membrane.Once the water is drained and the polymer is in contact with the membrane, the chamber can be unscrewed to allow the remaining water to evaporate. The total process, including setup and water draining, takes about 15 minutes, but this time can be shortened by increasing the draining rate and by constructing the chamber to require a smaller water volume. Shown here are films prepared by directly scooping them off of a water bath surface using the porous membrane.The tearing of the membrane and the placement off center are evident. The distance of the membrane center to the substrate center is shown on the right for various placed membranes. Here we see the improvement in reproducibility utilizing the drain chamber.The intact films are evident, and the distance of membrane center to substrate center is shown to be minimized. The drain chamber has reduced the chance of film tearing and folding over the manual method. A clean laboratory environment free from dust will limit incidental contamination.This method for thin film membrane transfer definitively reduces the damage done to the membrane and improves the accuracy and reproducibility of its placement on the substrate. By removing the difficult task of manipulating thin films on the water surface by hand, modifications to the basic drain chamber design can allow for the implementation of different polymer sample sizes and porous substrate types.

procedure-for-transfer-polymer-films-onto-porous-substrates-with

Research

JoVE Journal

Engineering

6.5K Views.  University of Chicago. Per studiare le pellicole sottili polimeriche nelle applicazioni a membrana, i materiali devono essere trasferiti da un substrato lucido e liscio a substrati porosi in un modo che non pieghi, rughe, strappi o deformi plasticamente il film. Questo video descrive una camera di scarico stampabile in 3D progettata per raggiungere questo obiettivo e riguarda i passaggi da quattro a sei nel flusso di processo mostrato qui. I campioni utilizzati in questo lavoro sono costituiti da substrati di wafer...