Photodiode for CIS (CMOS Image Sensor) in TSMC

[salehm]

Dear all,

Does TSMC 0.18um fabricate photodiode for image sensor application?

Tnx

 

[erikl]

Quite a lot of them, but mainly with smaller processes.
If you don't need BSI, you could well get along with the standard 0.18µm precision analog process, see e.g. this post.

 

[salehm]

Thanks for your kind attention!

Then, in the cadence, and tsmc library, there is no model for photodiode. What can I do if I want draw its layout? Can I draw a simple diode layout for photodiode layout? does it work after fabrication?

Regards

 

[erikl]

Can I draw a simple diode layout for photodiode layout? does it work after fabrication?

Sure it will work, see the a.m. thread. But of course you can't simulate its light sensitivity. If you can get hold of the proper process parameters, you could either simulate this with Silvaco's Luminous software (also mentioned in the a.m. thread), or (tediously) calculate it using the theoretical approach from the EE392B Lecture Notes -- and create your own model.

 

[salehm]

Thanks for the reply,

I have another question. Does standard CMOS technology put Micro Lens on the pixel array? Will imager work without micro lenses?

regards!

 

[erikl]

Does standard CMOS technology put Micro Lens on the pixel array?

No.

Will imager work without micro lenses?

The photo diodes will work. The imager is responsible to create the image from the photo diodes and the logistics to shift it out. It has nothing to do with the optical system -- the micro lenses -- which are responsible for the image geometry.