A special precaution has been made to reduce the FD capacitance by spacing it away from TG and making RST gate of trapezoidal shape:
The simulated CG of the jot is 380uV/e for a 1.4um pixel in 65nm process (FD capacitance of 0.4fF). The work was sponsored by Rambus.
Wondering why so many papers are published with just simulations and with the claim that the chip is in the foundry. I understand those who don't plan to fabricate it for time reasons or lack of funding. Isn't it better to wait few more months and publish a paper with experimental results and at an even better journal? It is not a critics towards this work, I think this is a nice paper, just trying to understand the publication policies of universities..
ReplyDeleteThank you for the nice comment. I can't speak for other universities, but in our case we think that the idea of the pump gate, distal FD, and other features, may be of interest for "regular" CIS devices. I think the risk of the device not working is small since TCAD is pretty good these days, but it might require several fab iterations for implant adjustments. You know that a new pixel probably costs a million dollars or more to fully develop. We just don't have that much of a budget. So, we share our ideas with the community, and we are taking a stab at fabbing it, thanks to our sponsor Rambus and the cooperation of TSMC. It will require a split from the regular process due to different implant conditions (same masks) and who knows when/if we will ever get a chip, much less a working chip, back. But we will keep our fingers crossed and if works well enough, we will write a follow up paper.
DeleteBy the way, one of the "products" of a research university is new knowledge and ideas. So, when I feel we have something worth sharing, we publish it. Most of this work was done by Jiaju Ma. (Nice job JJ!)
Why does the VB's potential change ? It's not under TX gate ... Thanks !
ReplyDelete-yang ni
Yang Ni - it is just a fringing-field effect from TG being turned on. You can see this better in Fig 9, I think.
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