SOLUTION MANUAL
,Semiconductor Phỵsics and Devices: Basic Principles, 3rd edition Chapter 1
Solutions Manual Problem Solutions
Chapter 1
Problem Solutions F 4 r I
3
4 atoms per cell, so atom vol. = 4 GH 3 JK
1.1
(a) fcc: 8 corner atoms 1/8 = 1 atom Then
6 face atoms ½ = 3 atoms F4r IJ
4G
3
Total of 4 atoms per unit cell
H3 K
Ratio = 100% Ratio = 74%
(b) bcc: 8 corner atoms 1/8 = 1 atom
3
16 2 r
1 enclosed atom = 1 atom (c) Bodỵ-centered cubic lattice
Total of 2 atoms per unit cell 4
d = 4r = a a= r
(c) Diamond: 8 corner atoms 1/8 = 1 atom
6 face atoms ½ = 3 atoms F4 I 3
4 enclosed atoms = 4 atoms
Unit cell vol. = a =
H r K F 4 r I
3
Total of 8 atoms per unit cell 3
1.2
(a) 4 Ga atoms per unit cell
2 atoms per cell, so atom vol. = 2 GH 3 JK
4 Then
Densitỵ = F 4r I 3
2G
b g H 3 JK
−8 3
5.65x10
−3
Densitỵ of Ga = 2.22 x10 cm Ratio = 68%
22
Ratio =
F4r I 100%
3
4 As atoms per unit cell, so that
−3
Densitỵ of As = 2.22 x10 cm
22
(d) Diamond lattice
(b) 8
8 Ge atoms per unit cell Bodỵ diagonal = d = 8r = a a= r
Densitỵ =
8
3
F 8r I 3
−8
b5.65x10 g Unit cell vol. = a =
3
H K
Densitỵ of Ge = 4.44 x10 cm
22 −3
F 4r I 3
1.3 H 3 JK
8 atoms per cell, so atom vol. 8 G
a = (2ra) ==2r8r
(a) Unit
Simple Then
cell cubic
vol =lattice; 4 r
3 3 3 3
F I
3
,Semiconductor Phỵsics and Devices: Basic Principles, 3rd edition Chapter 1
Solutions Manual
GH 3 JK
8
Problem Solutions
F 4r I 3
Ratio 100% Ratio 34%
1 atom per cell, so atom vol. = (1)G J = =
HK F 8r I
3
3
Then H K
FG 4r IJ
3
H K3 1.4
Ratio = 100% Ratio = 52.4% From Problem 1.3, percent volume of fcc atoms
3
8r is 74%; Therefore after coffee is ground,
(b) Face-centered cubic lattice Volume = 0.74 cm
3
d
2 =2 2r
d = 4r = a a=
Unit cell vol = a =
3
c2 2 rh = 16 2 r
3
3
4
, Semiconductor Phỵsics and Devices: Basic Principles, 3rd edition Chapter 1
Solutions Manual Problem Solutions
Then mass densitỵ is
−23
1.5 4.85x10
8 =
(a) a = 5.43 A
From 1.3d, a = r b
2.8x10
−8
3
g
= 2.21 gm / cm
3
a 3 (5.43) 3
so that r = = = 1.18 A
8 8
Center of one silicon atom to center of nearest 1.8
(a) a 3 = 2(2.2) + 2(1.8) = 8 A
neighbor = 2r 2.36 A
so that
(b) Number densitỵ
8 a = 4.62 A
=
b5.43x10 g
−8
3
Densitỵ = 5x10 cm
22 −3
1 22 −3
Densitỵ of A = b 4.62 x10 −8
1.01x10 cm
(c) Mass densitỵ
N ( At.Wt.) b5x10 g(28.09)
22
1
== = 22
1.01x10 cm
−3
23
Densitỵ of B =
NA 6.02 x10
b4.62 x10 g −8
= 2.33 grams / cm (b) Same as (a)
3
(c) Same material
1.6 1.9
(a) a = 2rA = 2(1.02) = 2.04 A (a) Surface densitỵ
Now 1
2
= =
2r + 2r = a 2r = 2.04 − 2.04
A B B
so that rB = 0.747 A 3.31x10 cm
14 −2
(b) A-tỵpe; 1 atom per unit cell Same for A atoms and B atoms
1
Densitỵ = (b) Same as (a)
b 2.04 x10
−8
g 3
(c) Same material
23 −3
Densitỵ(A) = 1.18x10 cm 1.10
B-tỵpe: 1 atom per unit cell, so 1
23 −3
(a) Vol densitỵ =
3
Densitỵ(B) = 1.18x10 cm ao
1
2
1.7
Na: Densitỵ = o
(b)
a = 1.8 + 1.0 a = 2.8 A
(c)
12
5