Ohmic contact & Passivation(오믹접합, 패시베이션)

소개

Ohmic contact & Passivation(오믹접합, 패시베이션)에 관련된 ppt 자료 입니다.

목차

Ohmic Contact - Introduction
Ohmic Contact - GaAs NonAlloy
HW (1) – Ag, Contact resistance
Ohmic Contact-Measurement(1)
Ohmic Contact-Measurement(2)
Ohmic Contact-Measurement(3)
HW(2)- TLM measurement
Ohmic - Equipment
Passivation-Introduction
Passivation-Equipment

본문내용

Ideal Ohmic contact
: No effect on device performance
: Purpose Minimize effect(Voltage drop, Contact resistance)
- Allow electrical current to flow into or out of the se miconductor.
Sequence of Ohmic contact
1. High doping
2. Cleaning(HF for Si, bromine-methanol for GaAs)
3. Metal deposition
4. Alloy
Ohmic Contact - GaAs Alloy(1)
1. Sequence of Ohmic contact
1. High doping
2. Cleaning(HF for Si, bromine-methanol for GaAs)
3. Metal deposition(improve Ni)
4. Alloy
2. Mechanism & Sequence of Alloy of AuGe
Heating the surface of the wafer
Ga(Ⅲ) diffuses into the metal -> AuGa
Ge(Ⅳ) diffuses into the wafer and acts as a dopant
Ni
Damage near the surface
Deposition of Ti. Ag, Mo
Overcoat of "thick" Gold
Ohmic Contact - GaAs Alloy(2)
Advantage of Alloy
Making n+ region
Lesser amount of arsenic evolve
Disadvantage of AuGe
Metal balling-up.
AuGa melts at blow alloy temp.
- Slip down the edge
- Irregular surface
Solution of AuGe problems
Ni, Ag
Deposition of Ti. Ag, Mo
Ohmic Contact - GaAs NonAlloy
1. Epitaxy layer(InGaAs, InAs) between
Metal and n-GaAs
: Emitter contact of GaAs HBT
Semicon
ductor

참고자료

· 없음