Photo developing defect and developing-like defect on DUV process

摘要

Three types of photo developing and developing-like defect on DUV process were presented in this paper. Scumming of photoresist on nitride film during developing process which was resulted from interaction between hyproduct of nitride film deposition process and resist that could not be removed by developer and water rinse. Those scumming developing defect would lead to bamboo shoots-like residue after etching that could cause microscratch during STI CMP. Either film treatment with HF vapor clean before photo process or adding extra rinse after hard backing can effectively eliminate those scumming defect. Splash from developer cup during water rinse process which appearance on non-resist area were crown-like on hydrophobic film could be reduced by extra rinse process after hard backing. Also owing to high contact angle between surfactant type developer and resist, discolor appearance on resist area would be formed after developing. Method to solve this issue was to apply developer as pre-wet before developing process.