Specific Process Knowledge/Thin film deposition/Furnace LPCVD Nitride: Difference between revisions

Revision as of 11:01, 4 December 2007

A few words about the furnace

The furnace is a Tempress horisontal furnace. The process is a batch process meaning you can run a batch of 25 wafers at a time. The deposition takes place at temperatures of 800-835 degrees Celsius. The reactive gases are Ammonia and dichlorsilane. The LPCVD nitride has a good step coverage and the film thickness is very uniform over the wafer. We have two standard LPCVD nitride processes: One for depositing stoichiometric nitride (Si₃N₄) and one for deposition of low stress nitride (SNR). To get information on how to operate the furnace please read the manual which is uploaded to LabManager.

Process Knowledge

Please take a look at the process side for deposition of Silicon Nitride using LPCVD: Deposition of Silicon Nitride using LPCVD

A rough overview of the performance of LPCVD Silicon Nitride and some process related parameters

Purpose	Deposition of silicon nitride	Stoichiometry: Si₃N₄ SRN SRN: Silicon Rich Nitride
Performance	Film thickness	Si₃N₄:~50Å - ~3000Å SRN: ~50Å - ~10000Å
.	Step coverage	Good
.	Film quality	Dense film Few defects
Process parameter range	Process Temperature	800-835 ^oC
.	Process pressure	80-230 mTorr
.	Gas flows	SiH $_{2}$ Cl $_{2}$ :10-100 sccm NH $_{3}$ :10-75 sccm
Substrates	Batch size	1-25 4" wafer per run deposition on both sides of the substrate
.	Substrate material allowed	Silicon wafers (new from the box or RCA cleaned) with layers of silicon oxide or silicon (oxy)nitride (RCA cleaned) Quartz wafers (RCA cleaned)

@@ Line 12: / Line 12: @@
 {| border="2" cellspacing="0" cellpadding="10"
 |-
-|Purpose ||Deposition of silicon nitride ||Stoichiometry:
+|style="background:silver; color:black"|Purpose ||style="background:LightGrey; color:black"|Deposition of silicon nitride ||style="background:WhiteSmoke; color:black"|Stoichiometry:
 *Si<sub>3</sub>N<sub>4</sub>
 *SRN
 SRN: Silicon Rich Nitride
 |-
-|Performance||Film thickness||
+|style="background:silver; color:black"|Performance||style="background:LightGrey; color:black"|Film thickness||style="background:WhiteSmoke; color:black"|
 *Si<sub>3</sub>N<sub>4</sub>:~50Å - ~3000Å
 *SRN: ~50Å - ~10000Å
 |-
-|||Step coverage
+|style="background:silver; color:black"|.||style="background:LightGrey; color:black"|Step coverage
-|
+|style="background:WhiteSmoke; color:black"|
 *Good
 |-
-|||Film quality
+|style="background:silver; color:black"|.||style="background:LightGrey; color:black"|Film quality
-|
+|style="background:WhiteSmoke; color:black"|
 *Dense film
 *Few defects
 |-
-|Process parameter range||Process Temperature
+|style="background:silver; color:black"|Process parameter range||style="background:LightGrey; color:black"|Process Temperature
-|
+|style="background:WhiteSmoke; color:black"|
 *800-835 <sup>o</sup>C
 |-
-|||Process pressure
+|style="background:silver; color:black"|.||style="background:LightGrey; color:black"|Process pressure
-|
+|style="background:WhiteSmoke; color:black"|
 *80-230 mTorr
 |-
-|||Gas flows
+|style="background:silver; color:black"|.||style="background:LightGrey; color:black"|Gas flows
-|
+|style="background:WhiteSmoke; color:black"|
 *SiH<math>_2</math>Cl<math>_2</math>:10-100 sccm
 *NH<math>_3</math>:10-75 sccm
 |-
-|Substrates||Batch size
+|style="background:silver; color:black"|Substrates||style="background:LightGrey; color:black"|Batch size
-|
+|style="background:WhiteSmoke; color:black"|
 *1-25 4" wafer per run
 *deposition on both sides of the substrate
 |-
-||| Substrate material allowed
+|style="background:silver; color:black"|.|| style="background:LightGrey; color:black"|Substrate material allowed
-|
+|style="background:WhiteSmoke; color:black"|
 *Silicon wafers (new from the box or RCA cleaned)
 **with layers of silicon oxide or silicon (oxy)nitride (RCA cleaned)