DC Diode Sputtering
- Deposition pressure : 0.5 to 10 Pa ( 5*10^-3 to 0.1 torr)
- Deposition rate : 0.02 to 0.2 E-6 m/min
- Depostion temperature : 100 to 300 C
- Simple, relative ease in fabrication and thickness uniformity over large area
- Realtively high deposition pressure and relatively high substrate temperature
Apply an ac voltage to electrodes, so the electrons lost from the insulator surface can be replenished
- Compare with DC glow discharge system, the RF system is :
Appilcations in VLSI :
- relatively high discharge system
- relatively high coating rates
- can deposit both conductive materials and insulating materials
- only additional need for sputtering conductors is for a blocking capacitor to prevent shorting the target to ground
- Deposition of SiO2 films
- in situ sputter removal of thin native-oxide layers from Si and Al surface before the deposition of overlying films.
- Frequency: min 100K to 1M Hz, mostly 13.56 MHz.