Specific Process Knowledge/Lithography/Descum: Difference between revisions
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=Plasma Asher 4= | =Plasma Asher 4= | ||
==Descum processing in plasma asher 4 & 5== | ==Descum processing in plasma asher 4 & 5== | ||
Descum of AZ 5214E on 100 mm wafers. The descum process was tested for single substrates, as well as 3 substrates, placed vertically in the glass boat. For the 3 substrates only the center substrate was used for testing, the front and back wafers were used as dummy wafers. | Descum of AZ 5214E on 100 mm wafers. The descum process was tested for single substrates, as well as 3 substrates, placed vertically in the glass boat. For the 3 substrates only the center substrate was used for testing, the front and back wafers were used as dummy wafers. | ||
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|- | |- | ||
! scope=row| Test results | ! scope=row| Test results | ||
| Ashing rate: 5.7 ±2.1 | | Ashing rate: 5.7 ±2.1 nm/min<br>Non-uniformity: 0.6 ±0.4% || Ashing rate: 3.8 ±1.6 nm/min<br>Non-uniformity: 0.4 ±0.2% | ||
|- | |- | ||
! scope=row| Wafers | ! scope=row| Wafers | ||
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! scope=row| Test average temperature | ! scope=row| Test average temperature | ||
| 33°C || 33°C | | 33°C || 33°C | ||
|} | |||
<br clear="all" /> | |||
[[File:PA_descum_single_v2.png|400px|thumb|Ashing amount and ashing rate when processing a single 100 mm wafer.|right]] | |||
'''Single wafer processing'''<br> | |||
{| class="wikitable" | |||
|- | |||
! Ashing time [min] !! 1 !! 2 !! 5 !! 10 !! 15 | |||
|- | |||
| Ashing amount [nm] || 5.2 || 6.2 || 35.1 || 72.3 || 87.1 | |||
|- | |||
| Ashing rate [nm/min] || 5.2 || 3.1 || 7.0 || 7.2 || 5.8 | |||
|- | |||
| Film thickness range, before descum [nm] || 11 || 12 || 10 || 11 || 9 | |||
|- | |||
| Pre-ashing non-uniformity [%] || 0.37 || 0.40 || 0.33 || 0.37 || 0.30 | |||
|- | |||
| Film thickness range, after descum [nm] || 10 || 10 || 12 || 19 || 33 | |||
|- | |||
| Post-ashing non-uniformity [%] || 0.33 || 0.33 || 0.41 || 0.66 || 1.18 | |||
|} | |||
<br clear="all" /> | |||
[[File:PA_descum_multi_v2.png|400px|thumb|Ashing amount and ashing rate when processing multiple 100 mm wafers. Test measured on the center of 3 wafers.|right]] | |||
'''Multi wafer processing'''<br> | |||
{| class="wikitable" | |||
|- | |||
! Ashing time [min] !! 1 !! 2 !! 5 !! 10 !! 15 | |||
|- | |||
| Ashing amount [nm] || 4.3 || 6.7 || 10.1 || 39.5 || 78.8 | |||
|- | |||
| Ashing rate [nm/min] || 4.3 || 3.4 || 2.0 || 4.0 || 5.3 | |||
|- | |||
| Film thickness range, before descum [nm] || 11 || 13 || 11 || 12 || 14 | |||
|- | |||
| Post-ashing non-uniformity [%] || 0.37 || 0.43 || 0.37 || 0.40 || 0.46 | |||
|- | |||
| Film thickness range, after descum [nm] || 11 || 9 || 10 || 12 || 21 | |||
|- | |||
| Post-ashing non-uniformity [%] || 0.37 || 0.30 || 0.33 || 0.41 || 0.74 | |||
|} | |} | ||