Specific Process Knowledge/Lithography/UVLithography: Difference between revisions
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** Positive tone resist: Resist exposed to UV light will be dissolved in the developer. The mask is an exact copy of the pattern which is to remain on the wafer. | ** Positive tone resist: Resist exposed to UV light will be dissolved in the developer. The mask is an exact copy of the 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 is an inverse copy of the 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 is an inverse copy of the pattern which is to remain on the wafer. | ||
::A list of UV lithography resist types available at DTU Danchip can be found [[Specific_Process_Knowledge/Lithography/UVLithography#Resist_Overview|on this page]]. | ::A list of UV lithography resist types available at DTU Danchip can be found [[Specific_Process_Knowledge/Lithography/UVLithography#Resist_Overview|on this page]]. | ||
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* '''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 not smaller than the thickness of the resist. Furthermore, when you decide for the resist thickness, consider which transfer you need: | * '''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 not smaller 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 thicknnesses ~5 times larger than the thickness of the metal to be lifted. | ** For [[Specific_Process_Knowledge/Lithography/LiftOff|lift-off]] processes, we recommend resist thicknnesses ~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 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]]. | |||
* '''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. | |||
* '''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]]. | |||
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