AN2386

MOS structure

13/30

If the silicon is doped of p-type (n-channel MOSFET) and the polysilicon is also doped of p-

type, (Equation 32),

Equation 43

and (Equation 39) becomes negative:

Equation 44

and, thus, (Equation 42) becames:

Equation 45

Φ

ms

kT

q

-------

N

g

N

a

•

ni

2

--------------------







ln

=

∂Φ

ms

∂T

-------------

Φ

ms

T

----------

3

K

q

----

•

–

E

go

qT

---------

–

=

∂V

TH

∂T

-------------

Φ

ms

T

----------

2

Φ

F

T

------

•

t

OX

ε

ε

OX

Φ

F

---------------------

•

∂Φ

F

∂T

---------

•

6

K

q

----

•

–

2

E

go

qT

---------

•

–

++

=