Semiconductor type: $q,$

Mode: $q,$

$(5)($Based on Neamen, Review Question $10\mathrm{.}11-10\mathrm{.}13)$

$($a$)$ Qualitatively sketch the inversion charge density in the channel region when an NMOS transistor is biased in the nonsaturation region. Draw a similar sketch when an NMOS transistor is biased in the saturation region.

$($b$)$ Define $V_{DS},$ sat in words

$($c$)$ Define an enhancement mode device and a depletion mode device $($for both NMOS and PMOS$).$ Give your answer in words