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Halbleiterphysik - Eine Zusammenfassung

Halbleiterphysik - Eine Zusammenfassung

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pn <br />

nn + <br />

pn <br />

<br />

<br />

<br />

<br />

<br />

pn <br />

<br />

<br />

<br />

pn <br />

pn


E = hf = ¯hω <br />

<br />

<br />

pq = E<br />

c<br />

E = pqc <br />

= hf<br />

c<br />

= h<br />

λ<br />

pq . . . c . . . <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

¯hω0 = ¯hωsc + Ee<br />

¯h −→ k 0 = ¯h −→ k sc + −→ p e<br />

Ee −→ p e <br />

<br />

−→ k <br />

<br />

<br />

<br />

¯h −→ k<br />

<br />

<br />

−→ k<br />

<br />

<br />

= 2π<br />

λ<br />

<br />

<br />

= h 2π h<br />

· =<br />

2π λ λ<br />

<br />

¯hω ¯hk


sin cos <br />

<br />

• ω(k)<br />

Ψ (x, t) = A. sin (x, t) = A. sin (k.x − k.v.t) <br />

• <br />

• <br />

• <br />

<br />

vg = ∂ω(k)<br />

∂k<br />

<br />

<br />

<br />

<br />

<br />

Ψ(x, t) = exp [i (k.x − ω.t)] <br />

E = ¯hω <br />

p = ¯hk <br />

E = p2<br />

2m<br />

<br />

<br />

<br />

i¯h ∂<br />

∂t Ψ(x, t) = EΨ(x, t)<br />

− ¯h2 ∂<br />

2m<br />

2<br />

∂x2 Ψ(x, t) = p2<br />

<br />

⇒ −<br />

2mΨ(x, t)<br />

¯h2 ∂<br />

2m<br />

2<br />

∂<br />

Ψ(x, t) = i¯h Ψ(x, t)<br />

∂x2 ∂t


− ¯h2 ∂<br />

2m<br />

2<br />

Ψ(x, t)<br />

∂x2 <br />

<br />

+ V (x, t).Ψ(x, t)<br />

<br />

<br />

<br />

△ = ∂2<br />

∂x<br />

= i¯h ∂<br />

Ψ(x, t)<br />

<br />

∂t<br />

<br />

<br />

∂y<br />

∂z 2<br />

∂2 ∂2<br />

+ + 2 2<br />

<br />

<br />

<br />

<br />

− ¯h2<br />

2m △ Ψ(−→ x , t) + V ( −→ x , t).Ψ( −→ x , t) = i¯h ∂<br />

∂t Ψ(−→ x , t) <br />

<br />

<br />

<br />

<br />

<br />

<br />

+∞<br />

−∞<br />

Ψ ∗ ( −→ x , t)Ψ( −→ x , t)dV = 1 <br />

<br />

<br />

<br />

Ψ(x, t) = 1<br />

<br />

√<br />

2π<br />

g(k) · e i(kx−ω(k)t) dk <br />

g(k) <br />

<br />

<br />

<br />

∆x · ∆px ≥ ¯h<br />

<br />

2<br />

<br />

<br />

<br />

<br />

Ψ( −→ x , t) = e −iωt · ϕ( −→ x ) <br />

<br />

− ¯h2<br />

2m △ ϕ(−→ x ) + V ( −→ x ).ϕ( −→ x ) = E · ϕ( −→ x )


ϕ(x) = 0 <br />

<br />

ϕ(x) = A. sin(kx) <br />

E(k) = ¯h2 k2 <br />

2m<br />

ϕ(x = 0) = ϕ(x = a) a <br />

<br />

k = nπ<br />

. . . (n = 1, 2, 3, . . .) <br />

a<br />

A <br />

<br />

<br />

ϕn(x) =<br />

<br />

2<br />

a sin<br />

<br />

nπx<br />

<br />

a<br />

<br />

En = ¯h2 π 2<br />

2ma 2 n2 <br />

L<br />

ϕl,j,n(x, y, z) =<br />

<br />

3<br />

2 2<br />

sin<br />

L<br />

<br />

lπx<br />

sin<br />

L<br />

<br />

jπx<br />

sin<br />

L<br />

<br />

nπx<br />

<br />

L<br />

En = ¯h2 π2 2mL2 2 2 2<br />

l + j + n <br />

<br />

<br />

V <br />

V <br />

<br />

<br />

ϕI(x) = A1e ikx + A2e −ikx<br />

ϕII(x) = B1e κx + B2e −κx<br />

ϕIII(x) = C1e ikx + C2e −ikx<br />

i II <br />

k κ <br />

Ai Bi Ci <br />

<br />

ϕI(x = 0) = ϕII(x = 0)<br />

ϕII(x = d) = ϕIII(x = d)<br />

∂ϕI<br />

∂x<br />

∂ϕII<br />

∂x<br />

∂ϕII<br />

(x = 0) = (x = 0)<br />

∂x<br />

∂ϕIII<br />

(x = d) = (x = d)<br />

∂x


⇒ C2 = 0<br />

⇒ A1 = 1<br />

<br />

<br />

ϕ(x) = A. exp(−ikx)<br />

Ψr(x, t) = A. exp(−ikx).exp(−iωt)<br />

R = Ψ ∗ r(x, t).Ψr(x, t)<br />

<br />

ϕ(x) = A. exp(+ikx)<br />

Ψt(x, t) = A. exp(+ikx).exp(−iωt)<br />

R = Ψ ∗ t (x, t).Ψt(x, t)<br />

<br />

<br />

<br />

1 = 10 −10 m<br />

<br />

<br />

<br />

<br />

V (r) = − e2<br />

4πε0r<br />

<br />

<br />

− ¯h2<br />

e2<br />

∆Ψ(r) − Ψ(r) = EΨ(r) <br />

2m 4πε0r<br />

∆ r θ ϕ <br />

<br />

<br />

Ψ(r, θ, ϕ) = R(r).Θ(θ).ϕ(ϕ) <br />

r θ ϕ n m l <br />

<br />

n = 1, 2, 3, . . . <br />

l = 0, 1, 2, . . . (n − 1) <br />

m = −l, −l + 1, . . . , 0, . . . l − 1, l


n <br />

En = − e2<br />

4πε0aB<br />

aB <br />

aB =<br />

· 1<br />

n 2<br />

<br />

2<br />

4πε0¯h<br />

= 0.053nm <br />

m0e2 <br />

4 m0e<br />

EB = − = −13.6eV <br />

2(4π¯hε0) 2<br />

<br />

±¯h/2 <br />

s = ± 1<br />

2<br />

<br />

<br />

<br />

<br />

<br />

<br />

¯hω = Em − En<br />

<br />

<br />

<br />

1<br />

¯hω = ER 12 − 1<br />

n2 <br />

<br />

<br />

1<br />

¯hω = ER 2<br />

n = 2, 3, 4, . . .<br />

2 − 1<br />

n2 <br />

<br />

<br />

¯hω = ER<br />

n = 3, 4, 5, . . .<br />

n = 4, 5, 6, . . .<br />

1<br />

3 2 − 1<br />

n 2


→ <br />

k k <br />

E(k)<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

Ψ = ΨH(r1) − ΨH(r2) Ψ = ΨH(r1) + ΨH(r2)<br />

<br />

<br />

<br />

E(k)<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

→ <br />

→ <br />

→ <br />

<br />

<br />

T = 0


→ <br />

→ <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

d <br />

Θ <br />

2d · sin(Θ) = n · λ <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

2π <br />

<br />

kl = lπ<br />

a<br />

l = ±1, 2, 3, . . . <br />

<br />

exp i −→ k · −→ <br />

x<br />

uk ( −→ x ) <br />

Ψk ( −→ x ) = uk ( −→ x ) · e i−→ k −→ x


a0 <br />

V (x + a0) = V (x) <br />

<br />

<br />

<br />

<br />

Ψk(x) = uk(x) · e ikx u(x) = u(x + a + b) <br />

<br />

k<br />

β 2 − α 2<br />

2αβ<br />

· sinh (βb) · sin (αa) + cosh (βb) · cos (αa) = cos (k (a + b)) <br />

α 2 = 2m<br />

¯h 2 E β2 = 2m<br />

¯h 2 (V0 − E)<br />

+1 −1 ⇒ <br />

+1 −1 <br />

<br />

<br />

<br />

<br />

<br />

P sin(αa)<br />

αa<br />

+ cos(αa) = cos(ka) <br />

P = ma<br />

¯h 2 · V0 · b<br />

P → 0 <br />

P → ∞ <br />

E(k) E(k) a, P =<br />

const. k α E(k)<br />

k = nπ<br />

a cos<br />

<br />

k = nπ<br />

a <br />

<br />

− π<br />

π<br />

a ≤ k ≤ + a<br />

− 2π<br />

a<br />

π ≤ k ≤ − a<br />

π<br />

2π<br />

+ a ≤ k ≤ + a<br />

E(k) <br />

→ <br />

k = ± 2π<br />

a


E(k)<br />

→ <br />

<br />

<br />

<br />

k q<br />

<br />

<br />

K<br />

ω(q) = 2<br />

M ·<br />

<br />

qa<br />

<br />

<br />

sin<br />

<br />

2<br />

<br />

<br />

<br />

<br />

<br />

<br />

ωac(q) = ω0<br />

<br />

<br />

√2 · 1 − 1 − γ2 2 aq<br />

sin<br />

2<br />

ωopt(q) =<br />

<br />

ω0<br />

<br />

<br />

√2 · 1 + 1 − γ2 <br />

2 aq<br />

sin<br />

2<br />

<br />

ω0 =<br />

(C1 + C2) (M1 + M2)<br />

γ<br />

M1M2<br />

2 = 16 C1C2<br />

2 ·<br />

(C1 + C2) M1M2<br />

(M1 + M2) 2 <br />

q


A + B − <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

En = n + 1<br />

<br />

¯hω<br />

2<br />

<br />

¯hω <br />

<br />

<br />

T <br />

<br />

n =<br />

exp<br />

1<br />

¯hω<br />

kBT<br />

<br />

− 1<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

[uvw] <br />

<br />

<br />

<br />

<br />

<br />

(hkl)<br />

<br />

<br />

<br />


• <br />

<br />

• <br />

<br />

• <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

Γ <br />

X <br />

L <br />

<br />

<br />

<br />

Γ <br />

<br />

EG


EC, EV <br />

ELeitungsband = EC + ¯h2 k 2<br />

2m∗ n<br />

EV alenzband = EV + ¯h2 k2 2m ∗ p<br />

<br />

<br />

<br />

<br />

ELeitungsband = EC + ¯h2 k2 1<br />

2m∗ +<br />

n1<br />

¯h2 k2 2<br />

2m∗ +<br />

n2<br />

¯h2 k2 3<br />

2m∗ n3<br />

<br />

k = 0 <br />

k = 0 <br />

IV − IV III − V <br />

<br />

<br />

m ∗ = ¯h 2 ·<br />

2 d E<br />

dk2 −1


1 1<br />

=<br />

m∗ ¯h 2<br />

⎡<br />

⎢<br />

⎣<br />

∂ 2 E<br />

∂k2 x<br />

∂ 2 E<br />

∂ky∂kx<br />

∂ 2 E<br />

∂kz∂kx<br />

∂ 2 E<br />

∂kx∂ky<br />

∂ 2 E<br />

∂k 2 y<br />

∂ 2 E<br />

∂kz∂ky<br />

∂ 2 E<br />

∂kx∂kz<br />

∂ 2 E<br />

∂ky∂kz<br />

∂ 2 E<br />

∂k2 z<br />

<br />

⎤<br />

⎥<br />

⎦<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

k


→ <br />

→ <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

→ <br />

<br />

ni <br />

n p <br />

<br />

p = n = ni(T ) <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

n p <br />

<br />

<br />

EC


→ <br />

<br />

D + + e → D ∗ <br />

→ <br />

→ → <br />

<br />

A ∗ → A − + h <br />

<br />

<br />

p <br />

n <br />

<br />

→ <br />

<br />

<br />

p · n = n 2 i <br />

<br />

p p = NA n = n 2 i /NA<br />

n n = ND p = n 2 i /ND<br />

<br />

<br />

E1 E2 n1 <br />

n2 <br />

n2<br />

n1<br />

<br />

= exp − E2 <br />

kT<br />

exp − E1<br />

<br />

= exp −<br />

kT<br />

E2<br />

<br />

− E1<br />

kT<br />

1<br />

f(E) = <br />

E−EF<br />

1+exp kT<br />

f(E) = exp − E−EF<br />

kT<br />

<br />

<br />

<br />

→ <br />

<br />

EF <br />

<br />

EF


Z(E) <br />

E <br />

<br />

dN(dkx, dky, dkz) = 2 ·<br />

k<br />

= <br />

k<br />

= 2 · dkx · dky · dkz<br />

2π<br />

L<br />

<br />

3<br />

= 2V · 4π · k2 dk<br />

(2π) 3<br />

E = ¯h2 k 2<br />

2m ∗ ⇒ k2 = 2m∗<br />

¯h 2 · E <br />

dE = ¯h2<br />

k · dk <br />

m∗ dN(E) = 2V<br />

(2π) 3<br />

4π<br />

¯h 3 (2m∗ ) 3 1<br />

2 E 2 · dE <br />

<br />

<br />

Z(E) · dE = dN(E)<br />

V<br />

<br />

Z(E) = 1<br />

(2π) 3<br />

4π<br />

¯h 3 (2m∗ ) 3 1<br />

2 E 2 <br />

<br />

<br />

∞<br />

n = f(E)Z(E)dE <br />

p =<br />

EV<br />

∞<br />

EC<br />

(1 − f(E))Z(E)dE <br />

<br />

< 1018cm−3 <br />

<br />

<br />

∞<br />

<br />

n = f(E)Z(E)dE ≈ NC · exp − EC<br />

<br />

− EF<br />

<br />

p =<br />

EV<br />

∞<br />

EC<br />

(1 − f(E))Z(E)dE ≈ NV · exp<br />

NC = 2<br />

¯h 3 (2πm∗ nkT ) 3<br />

2 NV = 2<br />

¯h 3<br />

NC NV <br />

<br />

kT<br />

<br />

− EF − EV<br />

kT<br />

2πm ∗ pkT<br />

<br />

3<br />

2


EF EC EF<br />

EV <br />

ND >> NC <br />

<br />

ni <br />

<br />

n 2 <br />

i = n · p = NCNV · exp − EC<br />

<br />

− EF<br />

<br />

kT<br />

EG <br />

<br />

n n > ni > p<br />

p n < ni < p<br />

<br />

<br />

> ni <br />

<br />

n · p = n 2 i<br />

<br />

ρ = e (p − n + ND − NA) = 0 <br />

n ND > NA<br />

n = ND<br />

<br />

− NA (ND − NA)<br />

+<br />

2<br />

2<br />

+ n<br />

4<br />

2 i<br />

p = − ND<br />

<br />

− NA (ND − NA)<br />

+<br />

2<br />

2<br />

+ n<br />

4<br />

2 i<br />

ni ND NA<br />

ND <br />

n =<br />

n 2 i<br />

NA − ND<br />

p = NA − ND


→ <br />

<br />

→ <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

hf ><br />

EC −EV G = Gth +GL <br />

n · p > n 2 i <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

αn αp <br />

<br />

τL <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

−→ −→ ∗<br />

F = e · E = m d−→ v<br />

dt + m∗−→ v<br />

τ<br />

d −→ v<br />

dt = 0 ⇒ m∗ · −→ v<br />

τ<br />

<br />

<br />

= e · −→ E


−→ j σ <br />

<br />

−→<br />

j = n · e ·<br />

−→<br />

v <br />

σ = e2 · n · τ<br />

m∗ −→<br />

j =<br />

−→<br />

σ · E<br />

<br />

<br />

µ <br />

µ =<br />

e · τ<br />

m∗ σ = e · n · µ<br />

<br />

<br />

<br />

<br />

−→ J n = e · n · −→ v n <br />

−→ J p = e · n · −→ v p <br />

<br />

−→ J = −→ J n + −→ J p = e (nµn + pµp) −→ E <br />

<br />

<br />

σ = e (nµn + pµp) <br />

→ <br />

<br />

<br />

<br />

<br />

∂f e<br />

−<br />

∂t ¯h E · ∇kf<br />

<br />

df<br />

+ v · ∇rf =<br />

dt<br />

<br />

f ∇k ∇r <br />

<br />

<br />

<br />

<br />

<br />

<br />

• <br />

• <br />

<br />

<br />

<br />

coll


vn = −µnE <br />

vp = +µpE <br />

<br />

<br />

1<br />

µ = 1<br />

<br />

µi<br />

i<br />

<br />

<br />

<br />

<br />

n →<br />

<br />

<br />

<br />

−→ F = ±e · −→ v × −→ B <br />

n p <br />

→ <br />

<br />

UH = 1 IB<br />

<br />

en Z<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

Jp =<br />

dp<br />

−eDp<br />

dx<br />

Jn =<br />

dn<br />

+eDn<br />

dx<br />

UT <br />

<br />

<br />

Dn = UT µn <br />

Dp = UT µp <br />

UT = kBT<br />

e


Jp =<br />

dp<br />

epµpE − eDp<br />

dx<br />

Jn =<br />

dn<br />

enµnE + eDn<br />

dx<br />

<br />

∂p<br />

∂t<br />

<br />

<br />

<br />

<br />

<br />

<br />

1 Jp(x) − Jp(x + ∆x)<br />

= + G − R <br />

e ∆x<br />

∂p 1 ∂Jp<br />

+<br />

∂t e ∂x<br />

∂n 1 ∂Jn<br />

−<br />

∂t e ∂x<br />

dE<br />

dx<br />

= G − R <br />

= G − R <br />

= ρ<br />

ε<br />

<br />

Lp <br />

exp<br />

<br />

<br />

x = 0 <br />

<br />

<br />

<br />

<br />

<br />

<br />

τd <br />

<br />

τd = ε<br />

<br />

σ<br />

<br />

<br />

τL >> τd <br />

<br />


¯hω = ∆E <br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

• <br />

<br />

• k <br />

<br />

¯hk →<br />

E(k)


¯hω <br />

Zj(ω) = 1<br />

2π 2<br />

(2mr) 3/2<br />

¯h 2<br />

¯hω − EG<br />

<br />

<br />

<br />

fabs = fv(E1) [1 − fc(E2)] <br />

fem = fc(E2) [1 − fv(E1)] <br />

<br />

fabs − fem = fv(E1) − fc(E2) <br />

<br />

σ<br />

α(ω) = σ(ω) · Zj(ω) · (fabs − fem) <br />

<br />

(fabs − fem) > 0 ⇒ <br />

⇒ <br />

EF c − EF v > EG<br />

<br />

<br />

<br />

<br />

rsp(ω) = σsp(ω) · Zj(ω) · fc(E2)[1 − fv(E1)]


m∗ <br />

<br />

<br />

<br />

<br />

<br />

<br />

Eex = EG − En


pn<br />

nn + <br />

<br />

<br />

<br />

<br />

dn<br />

UT<br />

Jn = eµnnE + eDn = 0 ⇒ E =<br />

dx n<br />

· dn<br />

dx<br />

<br />

ϕ − ϕ1 = −<br />

x<br />

x1<br />

Edx = UT<br />

pn<br />

x<br />

x1<br />

1 dn<br />

dx = UT<br />

n dx<br />

n<br />

<br />

<br />

n1<br />

1<br />

n dn = UT ln n<br />

n1<br />

<br />

<br />

n = n2 <br />

p = n1 <br />

UD = ϕ2 − ϕ1 = UT · ln NAND<br />

n 2 i<br />

<br />

n <br />

p U <br />

<br />

UD <br />

UD − U <br />

<br />

<br />

pn → <br />

UD UD + |U| <br />

<br />

<br />

<br />

<br />

<br />

x = −dp x = +dn <br />

<br />

<br />

Qp + Qn = −eNAdpA + eNDdnA = 0


NAdp = NDdn<br />

<br />

<br />

<br />

dn dp Emax <br />

<br />

1<br />

=<br />

N0<br />

1<br />

+<br />

NA<br />

1<br />

<br />

ND<br />

<br />

<br />

2εUD<br />

d = dn + dp =<br />

<br />

eN0<br />

<br />

<br />

<br />

pn<br />

<br />

p <br />

n <br />

p <br />

n <br />

Is <br />

I =<br />

<br />

U<br />

Is · exp<br />

<br />

− 1<br />

UT<br />

Is = Js · A = en 2 <br />

Dp<br />

i A<br />

LpND<br />

<br />

<br />

+ Dn<br />

<br />

LnNA<br />

• <br />

• <br />

• → <br />

<br />

<br />

<br />

p n lp ln <br />

Lp Ln <br />

<br />

n 2 i <br />

n 2 i ∝ exp<br />

<br />

− EG<br />

<br />

kT


pn<br />

<br />

<br />

U ∗ B ≈ εE2 max<br />

2eN0<br />

• <br />

<br />

<br />

<br />

• <br />

<br />

<br />

→ <br />

• <br />

→ <br />

→ <br />

pn<br />

<br />

• <br />

• <br />

• <br />

<br />

<br />

<br />

pn <br />

→ <br />

U = 0 <br />

<br />

U > 0 <br />

<br />

<br />

<br />

n p → <br />

<br />

<br />

p <br />

n <br />

<br />

<br />


A B A B <br />

<br />

<br />

<br />


npn n p <br />

n pnp n p<br />

<br />

<br />

<br />

BC n p<br />

p n <br />

BC<br />

<br />

<br />

<br />

<br />

IC = eDn <br />

∂n eDnnp<br />

<br />

∂x A = A <br />

W<br />

UBE np IC IC <br />

UCB UCB <br />

C B → → IC UCB<br />

<br />

<br />

<br />

B = IC<br />

IB<br />

<br />

<br />

<br />

• <br />

<br />

• BC → <br />

<br />

• <br />

<br />

<br />

• <br />

• <br />

<br />

• <br />

BE BC UCE IB <br />


IC = Is<br />

<br />

exp<br />

<br />

<br />

UBE<br />

UT<br />

<br />

−<br />

UBC<br />

UT<br />

<br />

<br />

<br />

<br />

n n <br />

UDS > 0 <br />

p <br />

<br />

<br />

UGD = UGS − UDS<br />

<br />

UGS ≤ 0 <br />

|UGD| > |UGS| <br />

D <br />

S → D S<br />

UDS UGS <br />

UDS <br />

<br />

<br />

UDSS


µ ∝ T −2 <br />

<br />

<br />

• <br />

• <br />

• <br />

<br />

• <br />

• <br />

• <br />

<br />

• <br />

• <br />

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