SEMICONDUCTOR DEVICE PHYSICS AND DESIGN

494 CHAPTER 10. COHERENT TRANSPORT AND MESOSCOPIC DEVICES

A

B

C

D

E 0

V 0

Ef

Ec

Vb

Vb

Vb

E

NERGY

DISTANCE

4.0

3.0

2.0

1.0

0.0

APPLIED BIAS (V)

A

B

C

D

C

URRENT

(mA)

Negative

resistance

region

(a)

(b)

Double barrier

resonant

tunneling

0.0 0.1 0.2 0.3 0.4

Figure 10.4: (a) A conceptual explanation of the operation of resonant tunneling devices showing
the energy band diagram for different bias voltages. (b) Negative resistance region in the current–
voltage characteristic for the resonant tunneling diode.