Specific Process Knowledge/Lithography/Strip: Difference between revisions
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==Process gas ratio for plasma asher 4 & 5== | ==Process gas ratio for plasma asher 4 & 5== | ||
[[File:PA_gas_mix_v2.png|320px|thumb|Ashing rate as function of gas mix ratio processing a single 100 mm wafer.|right]] | [[File:PA_gas_mix_v2.png|320px|thumb|Ashing rate as function of gas mix ratio processing a single 100 mm wafer.|right]] | ||
The ashing rate is related to the gas mix, usually expressed as percentage of nitrogen of the total amount of gas. | The ashing rate is related to the gas mix, usually expressed as percentage of nitrogen of the total amount of gas. | ||
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[[File:PA_gas_mix_fullBoat_v1.png|320px|thumb|Ashing rate as function of gas mix ratio when processing a full boat of 25 100 mm wafers.|right]] | |||
Test using a boat of 25 100 mm wafers in the center of the process chamber shows that 80% nitrogen gives the highest ashing rate. | Test using a boat of 25 100 mm wafers in the center of the process chamber shows that 80% nitrogen gives the highest ashing rate. | ||