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|here]]. | :A list of UV lithography resist types available at DTU Danchip can be found [[Specific_Process_Knowledge/Lithography/UVLithography#Resist_Overview|here]]. | ||
# '''Thickness of resist''': In general, it is recommended to work with an aspect ratio of ~1, i.e. where the widths of the pattern is in the same order of magnitude 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 with an aspect ratio of ~1, i.e. where the widths of the pattern is in the same order of magnitude than the thickness of the resist. Furthermore, when you decide for the resist thickness, consider which transfer you need: | ||
#* For lift-off processes, we recommend resist thicknnesses ~5 times larger than the thickness of the metal to be lifted. | #* For lift-off processes, we recommend resist thicknnesses ~5 times larger than the thickness of the metal to be lifted. | ||