Thick and Thin Film Technology:
Film Ics are broadly classified as Thick film and thin film
circuits. Thin films are the ones whose thickness vary from 50 to
20000 A and the thick films have thickness that vary between 125000 to
625000A. However, the thickness of the film is not a critical tool for
classifying, but the technology for fabricating the film classifies
whether the film is thin or thick film.
Only passive components like resistors and capacitors can be
fabricated using film technology. Conventional film circuits are made
by depositing film capacitors on a non-conducting substrate like glass
or ceramic and pre-fabricated active components.
Thin Film Technology:
Thin films provide greater precision in
component values. Thin film deposition can be done using any of the
following methods.
1. Vacuum Evaporation
2. Sputtering
3. Gas plating
4. Electroplating
5. Electroless plating
6. Silk Screening.
Vacuum Evaporation:
Vacuum Evaporation technique is same as
vapour deposition technique.
Cathode Sputtering:
Sputtering system
Sputtering uses a system that is identical to that used for vacuum
evaporation. The process of Sputtering is carried out at a very low
pressure.
The material to be deposited on the substrate is subjected to heavy
bombardment by the ions of a heavy inert gas , Viz argon.
These ions are accelerated by making the source material as the
cathode. The atoms are given out from the cathode through a low
pressure inert gas and finally deposited on the substrate.
The high energy possed by the particles, while landing on the
substrate results in a uniform coating over the substrate with good
crystal structure.
A D.C. potential of about 3KV is applied between the cathode and the
anode, Which produces a glow discharge from the cathode that fills
completely the interelectrode space
Film Ics are broadly classified as Thick film and thin film
circuits. Thin films are the ones whose thickness vary from 50 to
20000 A and the thick films have thickness that vary between 125000 to
625000A. However, the thickness of the film is not a critical tool for
classifying, but the technology for fabricating the film classifies
whether the film is thin or thick film.
Only passive components like resistors and capacitors can be
fabricated using film technology. Conventional film circuits are made
by depositing film capacitors on a non-conducting substrate like glass
or ceramic and pre-fabricated active components.
Thin Film Technology:
Thin films provide greater precision in
component values. Thin film deposition can be done using any of the
following methods.
1. Vacuum Evaporation
2. Sputtering
3. Gas plating
4. Electroplating
5. Electroless plating
6. Silk Screening.
Vacuum Evaporation:
Vacuum Evaporation technique is same as
vapour deposition technique.
Cathode Sputtering:
Sputtering system
Sputtering uses a system that is identical to that used for vacuum
evaporation. The process of Sputtering is carried out at a very low
pressure.
The material to be deposited on the substrate is subjected to heavy
bombardment by the ions of a heavy inert gas , Viz argon.
These ions are accelerated by making the source material as the
cathode. The atoms are given out from the cathode through a low
pressure inert gas and finally deposited on the substrate.
The high energy possed by the particles, while landing on the
substrate results in a uniform coating over the substrate with good
crystal structure.
A D.C. potential of about 3KV is applied between the cathode and the
anode, Which produces a glow discharge from the cathode that fills
completely the interelectrode space
