p-n-. p- p-n- :
ξ = - (x+xp), -xp x 0, | (3.6) |
NA- p- p-n-; - ( Si = 12, Ge = 16, GaAs = 10,9), - ( = 8,85410-12 /).
x = 0 p-n- :
ξ = - xp. | (3.7) |
ξ n- p-n- :
ξ = (x-xn), | (3.8) |
p-n- . p-n- (- xp 0) p- :
U(x) = (x + xp)2, -xp x 0. | (3.9) |
n- (0 - xn) :
U(x) = [ND (2 xn x - x2) + NA ], | (3.10) |
x = 0 :
U(0) = . | (3.11) |
(3.10) x = xn
= [ND + NA ]. | (3.12) |
' (3.12), n n0, p p0:
[ND + NA ]. | (3.13) |
p-n- NAxp = NDxn, , l = (xp+xn) :
(3.14) |
p-n- . p - :
xp = , | (3.15) |
n- :
xn = , | (3.16) |
- .
p-n - :
l = | xp | + | xn |, | (3.17) |
, . n+-p- p+-n- , . .
xp xn . , ND >> NA, xp >> xn l :
l = xp @ ; | (3.18) |
NA >> ND, xn >> xp e l :
|
|
l = xn @ . | (3.19) |
p-n- , :
l = . | (3.20) |
, :
. | (3.21) |
ij
p-n- . ξ :
ξ = (x - ). | (3.22) |
x = 0
ξ = - . | (3.23) |
p-n- p- , p-n- p- :
U(x) = . | (3.24) |
x = 0, p- :
U(0) = . | (3.25) |
,
l = 2xp = 2xn, xp = xn = . | (3.26) |
:
l = . | (3.27) |
:
l0 = | (3.28) |
p-n- :
l = = . | (3.29) |
p-n - , . :
l = , | (3.30) |
() ().
i p-n-
i p-n- i i i :
Cj00 = , - , | (3.31) |
Cj0 = , - . | (3.32) |
p-n- :
Cj = Cj0 S = , | (3.33) |
S p-n-, l .
i i p-n- :
Cj = Cj00 S = . | (3.34) |
i i U,
Cj0 = Cj00 = Cj00 , | (3.35) |
m - ii, i : m = 1/2 i ; m = 1/3 - ii.
i p-n- i i ND >> NA :
Cj = S . | (3.36) |
p-n- i i :
Cj = S . | (3.37) |