Specific Process Knowledge/Thin film deposition/Furnace LPCVD Nitride: Difference between revisions
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==Deposition of Silicon Nitride using LPCVD== | ==Deposition of Silicon Nitride using LPCVD== | ||
Danchip has two LPCVD (Low Pressure Chemical Vapour Deposition) furnaces <!--[[Specific Process Knowledge/Thin film deposition/B2 Furnace LPCVD Nitride|LPCVD furnaces]]--> that are dedicated for deposition of silicon nitride: A 6" furnace (installed in 2008) for deposition of stoichiometric nitride on 100 mm and 150 mm wafers | Danchip has two LPCVD (Low Pressure Chemical Vapour Deposition) furnaces <!--[[Specific Process Knowledge/Thin film deposition/B2 Furnace LPCVD Nitride|LPCVD furnaces]]--> that are dedicated for deposition of silicon nitride: A 6" furnace (installed in 2008) for deposition of stoichiometric nitride on 100 mm and 150 mm wafers, until April 2016 it's been decided to use for deposition of silicon rich (i.e. low stress) nitride. And it’s allowed to run the stoichiometric nitride process only for 150 mm wafers. And a 4" furnace (installed in 1995) that was mainly used for deposition of silicon rich nitride on 100 mm wafers, until April 2016 it's been decided to use only for stoichiometric nitride. In LabManager the two furnaces are named "Furnace: LPCVD nitride (6") (E3)" and "Furnace: LPCVD nitride (4") (B2)", respectively. Both furnaces are Tempress horizontal furnaces. | ||
Please be aware of that it is not allowed to deposit silicon rich nitride in the | Please be aware of that it is not allowed to deposit silicon rich nitride in the 4" nitride furnace to avoid problems with particles. The 6" nitride furnace is mainly dedicated for deposition of silicon rich nitride. And please check the cross contamination information in LabManager before you use any of the two furnaces. | ||
The LPCVD silicon nitride deposition is a batch process, where nitride can be deposited on a batch of up to 25 wafers (in the 6" nitride furnace) or 15 wafers (in the 4" nitride furnace) at a time. The deposition takes place under vacuum (120-200 mTorr, depending on the process) and at temperature (780-845 C, depending on the process). The reactive gases are ammonia (NH<sub>3</sub>) and dichlorsilane (SiH<sub>2</sub>Cl<sub>2</sub>). The LPCVD nitride has a very good step coverage, and the film thickness is very uniform over the wafers. | The LPCVD silicon nitride deposition is a batch process, where nitride can be deposited on a batch of up to 25 wafers (in the 6" nitride furnace) or 15 wafers (in the 4" nitride furnace) at a time. The deposition takes place under vacuum (120-200 mTorr, depending on the process) and at temperature (780-845 C, depending on the process). The reactive gases are ammonia (NH<sub>3</sub>) and dichlorsilane (SiH<sub>2</sub>Cl<sub>2</sub>). The LPCVD nitride has a very good step coverage, and the film thickness is very uniform over the wafers. | ||