Specific Process Knowledge/Lithography/UVLithography: Difference between revisions
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* '''Resist Type''': Choose the type of resist you wish to use: a list of UV lithography resist types available at DTU Danchip can be found [[Specific_Process_Knowledge/Lithography/UVLithography#Resist_Overview|on this page]]. | * '''Resist Type''': Choose the type of resist you wish to use: a list of UV lithography resist types available at DTU Danchip can be found [[Specific_Process_Knowledge/Lithography/UVLithography#Resist_Overview|on this page]]. | ||
** Positive tone resist: Resist exposed to UV light will be dissolved in the developer. The mask | ** Positive tone resist: Resist exposed to UV light will be dissolved in the developer. The mask openings are an exact copy of the resist pattern which is to remain on the wafer. | ||
** Negative tone resist: Resist exposed to UV light will become polymerized and difficult to dissolve. The mask | ** Negative tone resist: Resist exposed to UV light will become polymerized and difficult to dissolve. The mask openings are an inverse copy of the resist pattern which is to remain on the wafer. | ||
* '''Thickness of resist''': In general, it is recommended to work at or below an aspect ratio of ~1, i.e. where the width of the pattern is | * '''Thickness of resist''': In general, it is recommended to work at or below an aspect ratio of ~1, i.e. where the width of the pattern is larger than the thickness of the resist. Furthermore, when you decide for the resist thickness, consider which transfer you need: | ||
** For [[Specific_Process_Knowledge/Lithography/LiftOff|lift-off]] processes, we recommend resist | ** For [[Specific_Process_Knowledge/Lithography/LiftOff|lift-off]] processes, we recommend resist thickness ~5 times larger than the thickness of the metal to be lifted. | ||
** For dry or wet etch processes, investigate the resist etch rate of your process as this might limit the minimum thickness of your resist. | ** For dry etch or wet etch processes, investigate the resist etch rate of your process as this might limit the minimum thickness of your resist. | ||
*'''Exposure''': Choose which mask aligner you wish to use; you can find a list of mask aligners [[Specific_Process_Knowledge/Lithography/UVExposure|here]]. | *'''Exposure''': Choose which mask aligner you wish to use; you can find a list of mask aligners [[Specific_Process_Knowledge/Lithography/UVExposure|here]]. Consider the exposure dose. | ||
* '''Mask''': Design and order a photomask for your UV process. A detailed instruction on how to design and order a photomask can be found [[Specific_Process_Knowledge/Lithography/Pattern_Design_and_Mask_Fabrication|here]]. | * '''Mask''': Design and order a photomask for your UV process. A detailed instruction on how to design and order a photomask can be found [[Specific_Process_Knowledge/Lithography/Pattern_Design_and_Mask_Fabrication|here]]. | ||
* '''Development''': Choose which equipment you wish to use to develop your photoresist from [[Specific_Process_Knowledge/Lithography/Development|this]] list. | * '''Development''': Choose which equipment you wish to use to develop your photoresist from [[Specific_Process_Knowledge/Lithography/Development|this]] list. Remember the development process (chemistry) influences the exposure dose. | ||
* '''Specify whether you wish to strip or lift-off your resist''': [[Specific_Process_Knowledge/Lithography/Strip|strip]] and [[Specific_Process_Knowledge/Lithography/LiftOff|lift-off]]. | * '''Specify whether you wish to strip or lift-off your resist''': [[Specific_Process_Knowledge/Lithography/Strip|strip]] and [[Specific_Process_Knowledge/Lithography/LiftOff|lift-off]]. | ||