Page 15 - Power Electronics Handbook

8 Power semiconductor devices
x
Control valve Clean
area

I-

I I
\ Quartz Quartz
boat with tube
I * Heater silicon slices

t

E
.- E
.-
c
c
!! !!
c
c
E
E
Increasing
8 8 Increasing
8 8
.o .o
a
a
n
n
- -
E E
Distance
Distance from Surface
from
Surface
t
-
C
P
0
L
C Increasing
E:
b
'C
-
3
E
Distance from surface
~
(C)
Figure 1.2 Semiconductor diffusion: (a) open-tube arrangement; (b) impurity concentration
using error function; (c) Gaussian impurity concentration