Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Large pixel pinned photodiode with small diodes

Status
Not open for further replies.

mehdinoormohammadi

Newbie level 6
Joined
Jan 23, 2013
Messages
11
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,516
Hello everyone,

I need to layout one pixel 300um*300um pinned photodiode which is quite large. I was wondering if anyone let me know it is possible to come up with small pinned photodiodes in parallel (50um*50um). Would there be charge sharing effects or any problems? I will use it with a dummy diode, thereby they would be interdigitated to reduce any mismatch.

Regards,
 

Other than a different periphery-area ratio probably no big
deal - but much of the art of (low noise, high sensitivity)
imager pixel design is in the periphery, bending junctions
away from surface traps and so on. You would be maybe
36 times as sensitive to -that- as a result of downscaling
the pixel X/Y dimension. But how much it matters will
depend a lot on the technology and the application
environment.

300um is not large, really. Check out Hamamatsu et al,
folks who sell single photodiodes. Pics may give you
some ideas about art.
 

Thanks for your reply,
I have attached the image showing how the small size (50um*50um) sensing PPN pixels are connected together to build up a large pixel (e.g., 300um*300um). Since the outputs of them are conencted together, any concern about charge sharing or other problems when TGs are on to transfer the charge from PPN to the FD node (n+).

PPN.jpg
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top