polySi LPCVD
rate (A/min) vs temperature (°C)

Si LPCVD
rate (nm/ min) vs temperature (°C)
580° - 620°C: transition region

Raman spectrum
Microcrystalline growth at the transition temperature
combination of crystalline structures and amorphous pockets
(measured at 3 different positions across the wafer)

LPCVD technology
(plasma for cleaning)

Equipment:
Plasmalab System 100/ 133

Technology:
Parallel Plate Reactor
Shower Head Gas inlet
SiH₄ based process

Results:
LPCVD of polycrystalline silicon at 650°C
Rate : 2 nm/min ( 20 nm/ min for PECVD)
Uniformity: ca +/-5 % across 100 mm wafer

XRD and Raman analysis of the as deposited films
demonstrate the crystalline nature of the films:
grain sizes > 100 nm and a degree of crystallinity > 80 %.
The polysilicon films grow preferentially along <1 1 0>
orientation and crystallization occurs along <1 1 1> orientation.

for more information download the paper:
http://www.oxfordplasma.de/pla_news/polysili.pdf