Specific Process Knowledge/Lithography/Development: Difference between revisions
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==Developer: SU8== | ==Developer: SU8== | ||
[[Image:SU-8developer.jpg|300x300px|right|thumb|The SU8-Developer bench is located in C-1]] | [[Image:SU-8developer.jpg|300x300px|right|thumb|The SU8-Developer bench is located in C-1]] | ||
The SU8-Developer bench is a manually operated chemical bench for submersion development of SU-8 photoresist in PGMEA (supplied in the cleanroom as mr-Dev 600). The development process is in two stages; one bath (FIRST) to dissolve the bulk of the resist, and a second, cleaner bath (FINAL) to finish the development. The development time is controlled manually by the user. After development, the substrates are rinsed with IPA and dried in the bench. | The SU8-Developer bench is a manually operated chemical bench for submersion development of SU-8 photoresist in PGMEA (supplied in the cleanroom as mr-Dev 600). The development process is in two stages; one bath (FIRST) to dissolve the bulk of the resist, and a second, cleaner bath (FINAL) to finish the development. The development time is controlled manually by the user. After development, the substrates are rinsed with IPA and dried in the bench. | ||
The user manual, user APV, and contact information can be found in [http://labmanager.dtu.dk/function.php?module=Machine&view=view&mach=154 LabManager] - '''requires login''' | |||
===Process information=== | ===Process information=== | ||
Several aspects of the outcome of SU-8 processing are affected by the development process. The lithographic resolution is affected by the time between PEB (post-exposure bake) and development, as the cross-linking process continues in the interface between exposed and unexposed regions even at room temperature. Cracks in the structures is affected by two things; the development time, and how much has previously been developed in the developer bath. Cracking is worse with longer development time, and worst in a new developer bath. The effect of the developer use quickly saturates (5-10 wafers). Finally, the stability of fine structures (high aspect ratio) is affected by the rinse after development, as the lower surface tension of IPA compared to PGMEA reduces pattern collapse during drying. | Several aspects of the outcome of SU-8 processing are affected by the development process. The lithographic resolution is affected by the time between PEB (post-exposure bake) and development, as the cross-linking process continues in the interface between exposed and unexposed regions even at room temperature. Cracks in the structures is affected by two things; the development time, and how much has previously been developed in the developer bath. Cracking is worse with longer development time, and worst in a new developer bath. The effect of the developer use quickly saturates (5-10 wafers). Finally, the stability of fine structures (high aspect ratio) is affected by the rinse after development, as the lower surface tension of IPA compared to PGMEA reduces pattern collapse during drying. | ||
Development time is strongly dependent on the SU-8 thickness. | Development time is strongly dependent on the SU-8 thickness. | ||
*Minimum development time: 1 min per | *Minimum development time: 1 min per 20 µm in FIRST | ||
Suggestions: | Suggestions: | ||
*2-5µm: 2 min. in FIRST; 2 min. in FINAL | *2-5µm: 2 min. in FIRST; 2 min. in FINAL | ||