oxide roughness results

[Filip Crnogorac]

Hi STS users,

here is roughness data for PECVD SiO2 running both the low and high  
frequency recipes (after a chamber clean). All data by 5x5um AFM  
tapping scan & roughness analysis.

std_lfox (tap = 5, not 4)
time = 3:00
deposited = 105.6 nm +-0.03
dep rate = 371 A/min
roughness (rms) = 0.390 nm
Z range = 4.1 nm

std_hfox
time = 3:00
deposited = 104.2 nm +-0.02
dep rate = 347 A/min
roughness (rms) = 0.680 nm
Z range = 8.2 nm

for comparison, thermal SiO2 has rms roughness close to 0.1 nm, while  
bare Si wafer is usually 0.1 nm or less.

Depositing with the chamber not clean gives similar roughness, but  
lower dep rates (352 A/min and 320 A/min).

If anyone would like to see the AFMs let me know.

Take care,

Filip

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Ph.D. Candidate, Stanford University
Department of Electrical Engineering
Center for Integrated Systems
B-103, 420 Via Palou
Stanford, CA 94305