. /.
- , .
, 4.1
/ (. 4.1)
. 4.1.
:
m = - Dm grad m (4.1)
m .
( )
m = - Dm (dm/dx) (4.2)
: (1/2*) , (.. )
Dm (2/), .
: Dn Ge=0.01 2/, Dn GaAs=0.025 2/ Dn Si=0.0033 2/
(j = I/S)
Jn = qDn grad n; Jp =qDp grad p (4.3)
n, p /.
. .
, , = 2,718... , (L).
, , .
Ln = (Dn tn)0,5 Lp = (Dp tp)0,5 (4.4)
: tn=10-7- 10-9c
L= (10-9c*0.01 2/)0,5=3 10-6
l .
: VT=105/, t=10-11-10-12, l=10-6-10-7
Dn = (kT/q)mn = fT mn Dp =(kT/q)mP = fT mP (4.5)
fT () , =300.
fT = 0.026 (26 )
/
, ; - ; , .
|
|
*) - .
,
( ), , , .
!!! - .
, .
- , .
` n . .
= ||m (4.6)
m = 5 - 8.
, --> .
,
( )
, .
, t / .
(.4.2).
( ).
/ =106/-Si, =105 / Ge.
.
.
( /, I ( ) .
. 4.2
/.
, .
, , .
.
. . , ,
|
|
Dn = RbNtn (4.7)
R -
b - , . . ( ), ;
N - , ( , hg);
N = Ps/hg (4.8)
tn -
, , , , (.4.3).
.
. 4.3
, , .
, , .
,
.
, , , , .
0 = qnmnE + qDn grad n + qpmpE qDP grad p (4.9)
grad p = grad n
E = -grad n(p) (Dn - DP) / (nmn + pmp) (4.10)
. . .