Specific Process Knowledge/Lithography/EBeamLithography/EBLsubstratePrep: Difference between revisions

We recommend all groups or users to have their own bottle of e-beam resist inside the cleanroom. Please follow the [[Specific Process Knowledge/Lithography/EBeamLithography/ResistBottles|user resist bottles in the cleanroom guide.]]

|'''Technical reports'''

|'''Spin Coater'''

|'''Thinner'''

|'''Developer'''

|[https://www.allresist.com/wp-content/uploads/sites/2/2020/03/AR-P6200_CSAR62english_Allresist_product-information.pdf AR-P 6200 info]  

|[[Specific_Process_Knowledge/Lithography/Coaters#Spin Coater: Gamma E-beam and UV|Spin Coater: Gamma E-beam and UV]] or [[Specific_Process_Knowledge/Lithography/Coaters#Manual_Spin_Coaters|Spin Coater: LabSpin 02/03]]

|Anisole

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|IPA

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|[https://www.allresist.com/wp-content/uploads/sites/2/2020/03/SXAR-N8200-1_english_Allresist_product_information.pdf AR-N 8200 info]

|[[Specific_Process_Knowledge/Lithography/Coaters#Manual_Spin_Coaters|Spin Coater: LabSpin 02/03]]

|AR 600-07

|AR 300-47:DIW (1:1)

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|Negative

|[http://www.allresist.com AllResist]

|[[Specific_Process_Knowledge/Lithography/Coaters#Manual_Spin_Coaters|Spin Coater: LabSpin 02/03]]

|PGMEA

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It is possible to obtain permission to user other resists at DTU Nanolab, users must however provide these resists and possibly developers themselves. A non-exhaustive list of user supplied EBL resist used at DTU Nanolab and some process guidelines can be found in the table below.

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|Negative

|[http://www.allresist.com AllResist]

|PGMEA

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|-style="background:WhiteSmoke; color:black"

|AR-P 6200.04

| 2026

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As exposure is done with an electron beam, insulating substrates will cause a build up of charge that will deflect the incoming beam and disturb pattern definition. It is therefore necesarry when working with insulating substrates or substrates with thick (> 200 nm) dielectric films to apply a discharge layer. This is typically applied on top of the EBL resist layer and must be removed in between exposure and development. The most common discharge layer is 20 nm thermally evaporated Al. Bear in mind that it should be thermally evaporated and not e-beam evaporated. Thermal evaporation of Al can be done in [[Specific_Process_Knowledge/Thin film deposition/thermalevaporator|Thermal evaporator]] and [[Specific_Process_Knowledge/Thin film deposition/Wordentec|Wordentec]]. The Al layer can be removed with MIF726 after exposure. MIF726 etch rate in Al is about 0.5 nm/s, although only about 1 nm/min in oxidized aluminium.

For samples with 2D materials such as graphene, HBN, etc., it is '''mandatory''' to apply a 20 nm Al layer on top of the resist in order to expose the substrate in the JEOL 9500 system. The Raith eLine system does not have this requirement.

Post exposure pattern dimensions are dependent on resist thickness. Thus, it is advisable to verify resist thickness after spin coating. This can be done by ellipsometry in the [[Specific_Process_Knowledge/Characterization/Optical_characterization#Ellipsometer|VASE Ellipsometer]].