Analysis of Polymer Formation during SiO 2 Microwave Plasma Etching
The mechanism of C x F y fluorocarbon deposition during SiO 2 etching is analyzed using a test sample with an overhang mask. For C 4 F 8 , CHF 3 , and CH 2 F 2 , only C x F y deposition was observed at 0 W of substrate-bias rf power, and the deposition profiles were similar. At a higher rf power, re...
Saved in:
| Published in | Japanese Journal of Applied Physics Vol. 34; no. 4S; p. 2132 |
|---|---|
| Main Authors | , |
| Format | Journal Article |
| Language | English |
| Published |
01.04.1995
|
| Online Access | Get full text |
Cover
Loading…
| Summary: | The mechanism of C
x
F
y
fluorocarbon deposition during SiO
2
etching is analyzed using a test sample with an overhang mask. For C
4
F
8
, CHF
3
, and CH
2
F
2
, only C
x
F
y
deposition was observed at 0 W of substrate-bias rf power, and the deposition profiles were similar. At a higher rf power, reaction phenomena changed to those of SiO
2
etching. The standard deviation σ of the etching-ion incident angle was measured as less than 2°. On the other hand, σ
d
e
p
o
measured from the deposition profile was about 20°. This difference may be caused by surface migration. This migration is thought to be a key factor in excess deposition at the bottom of a high-aspect-ratio hole. Etching rates of the deposit increased in the order of C
4
F
8
>CHF
3
>CH
2
F
2
. Therefore, SiO
2
-etching gases, such as C
4
F
8
, which form easily removable deposits, reduce RIE lags for contact hole patterning. |
|---|---|
| ISSN: | 0021-4922 1347-4065 |
| DOI: | 10.1143/JJAP.34.2132 |