MMIC FABRICATION TECHNIQUE

MMIC  FABRICATION  TECHNIQUES

1.       Doping techniques

2.       Epitaxial grouth

3.       Lithography

4.       Etching

5.       Metalfilm deposition

6.       Oxidation

7.       Filom deposition                           

Doping techniques:

Diffussion and ion implitation are two main techniques

1.diffussion techniques

The process of diffussion consist of diffussing impurities into a pure metal in order to aleter the basic electronic characteristics of pure metal.

2.ion imlation is process introduction of high enrgy charged’

dopant atom vaporized

enerigis lie between 30 to 300

*advantage of ion implatation

-accurate control of dopant dose and implantation

-posibility of light doping

-high uniformly over wafer

-good reproductilbility

2. Epitaxial Growth

-grouth of thin crystline substarte

*three types of epitaxial process

1.vapor –phase epitaxy

2.molecular –beam epitaxy

3.liquied-phase epitaxy

3.Lithography

Transffring pattern of geometric shapes through a mask to thin layer

The exposing radiation are uv rays,electrons,x-rays,ions

-four types of lithography

1.optical lithography

2.electron beam lithography

3.ion beam lithography

4.x-ray lithography

4. Metal film deposition

Metal Films deposition can be formed by various methods like physical vapour deposotion

PVD is commonly used for making MMIC

PVD TYPES

1.Evaporation

2.sputtering

5.Oxidation

Chemical process

In film depositon chemical vapor deposition techniques is used for semiconductor processing.