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Modeling >> Semiconductor Devices >> MOS varactor with diffusion layer
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Message started by newic on Mar 29^th, 2012, 7:02pm

Title: MOS varactor with diffusion layer
Post by newic on Mar 29^th, 2012, 7:02pm

want to know more on the accumulation type MOS varactor. (with nwell)

is n+ diffussion layer required beneath the poly layer?
I saw some varactor structures come with & without diffusion layer under the poly.

what is the purpose to have diffusion under the poly?

Title: Re: MOS varactor with diffusion layer
Post by nxing on Apr 5^th, 2013, 8:56am

under the poly, it's N-well, to form the accumulation varactor. Can you point to where people put n+ under gate? I personally never saw that.