Hi Andrea,

Based on your info, I would suggest you to check:

- wafer cleaning prior to coating to ensure the surface is hydrophilic.
- Don't know if S1813 PR needed prime promoter or not but you may try either
   HMDS or Surpass to see if it help enhance adhesion.
- Check post Develop to see if pattern were well defined or over exposed
- Check developer temp or if developer tool is running properly

Just a quick suggestion.

Hope this helps,
Paul


> Am 07/09/2010 15:58, schrieb Andrea Mazzolari:
>
>> Hi all,
>>
>> here i have (110) silicon wafers coated with silicon nitride.
>> I patterned the silicon nitride and etched the wafers in KOH and obtained
>> silicon pieces of lateral size 20x70mm.
>>
>> I need to pattern the silicon nitride on such silicon pieces.
>> I cleaned the silicon pieces with acetone/IPA then RCA1 and RCA2 to remove
>> any residue. I coated the silicon pieces with S1813 photoresist and tried
>> to pattern the silicon nitride with BHF. After sometime the PR is removed
>> from the silicon pieces.
>>
>> I suppose the starting silicon pieces were not correctly cleaned. Any
>> suggestion on how to improve the cleaning ?
>>
>> Best regards,
>> Andrea