'Parasitic' Photo Diodes in Genral Purpose TSMC 180nm CMOS

Modern CMOS image sensor (CIS) are realized in highly specialized semiconductor production processes that provide microscopic photo pixels allowing extremly high quality photo-sensing: the noise level is actually measured in just a few quanta of electron charges. However, these production processes are generally a well guarded secret, costly, and not easily available for academic research groups. Thus, we have for some time used general purpose CMOS processes instead to make experimental image sensors. That is possible becasue basically any PN-diode on a CMOS chip is sensitive to light and can be repurposed as a light sensor.

The goal of this project is to characterize candidates for 'parasitic' photo diodes in the general purpose TSMC 180nm CMOS process that our group has access to for a reasonable cost and production time cycle. We have thus used this process for master student projects in general and are considering using it for image sensor projects. The tasks will include the design of photo-pixel variants, to do layout, a tape-out to send the structures for production and to test the produced integrated circuit for light sensitivity and noise level. Future projects will benefit from finding one or several good solutions.

Emneord: CMOS, Integrated circuits, image sensor
Publisert 23. okt. 2020 14:45 - Sist endret 23. okt. 2020 14:45

Omfang (studiepoeng)