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    why pmos threshold bigger than its nmos couterpart?

    I mean abosulute value. Why this happens? Can anyone tell me ,thank you!

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    why pmos threshold bigger than its nmos couterpart?

    it is due to mobility of the carrier that forms the channel...


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    Re: why pmos threshold bigger than its nmos couterpart?

    A well-known formula for the threshold volatge:



    Fermi potential:




    It is not an accurate formula, but it pushes you to the right way.

    Usually the difference between the PMOS and NMOS threshold voltages is approx. 100 mV.
    I doubt it is because of the mobility.
    I guess it is because of the differences in doping.


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    why pmos threshold bigger than its nmos couterpart?

    I think it depends on vth implant by the foundry.



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    why pmos threshold bigger than its nmos couterpart?

    PMOS have two doping i,NWELL implant and P+ implant.



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    why pmos threshold bigger than its nmos couterpart?

    Hi
    I think the threshold voltage of NMOS and PMOS can be modified to a same level by the doping.



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    why pmos threshold bigger than its nmos couterpart?

    I think, too...Possible to make a techology with same threshold voltages.

    But I guess it is not so important and determine a technology is a trade-off between many things.
    Doping level is very important in breakdown, resistance , etc.



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    why pmos threshold bigger than its nmos couterpart?

    Yes, PMOS threshold for absolute value can be changed less than NMOS with threshold implant.



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