Chemical vapor deposition process for depositing tungsten
AssigneeApplied Materials, Inc.
InventorsRavi Rajagopalan, Steve Ghanayem, Manabu Yamazaki, Keiichi Ohtsuka, Yuji Maeda
Life of this patent
Estimating the term…
Abstract
A multiple step chemical vapor deposition process for depositing a tungsten layer on a substrate. A first step of the deposition process includes a nucleation step in which WF.sub.6 and SiH.sub.4 are introduced into a deposition chamber. Next, the flow of WF.sub.6 and SiH.sub.4 are stopped and diborane is introduced into the chamber for between 5-25 seconds. Finally, during a bulk deposition step, the WF.sub.6 is reintroduced into the chamber along with H.sub.2 and B.sub.2 H.sub.6 flows to deposit a tungsten layer on the substrate. In a preferred embodiment, the bulk deposition step also introduces nitrogen into the process gas.
Claims23
A chemical vapor deposition process for depositing a tungsten film on a substrate, said process comprising:
- (a) placing a substrate in a deposition zone;
- (b) introducing a tungsten-containing source and a first reduction agent into said deposition zone during a nucleation process stage;
- (c) during a first process stage after said nucleation process stage, introducing a group III or V hydride into said deposition zone without introducing a tungsten-containing source into said deposition zone;
- and
- (d) during a second process stage after said first stage,
- (i) introducing a process gas comprising a tungsten-containing source, a group III or V hydride and a second reduction agent into said deposition zone, and
- (ii) maintaining the deposition zone at process conditions suitable for depositing a tungsten layer on said substrate.
A chemical vapor deposition process for depositing a tungsten film on a substrate, said process comprising:
- (a) placing a substrate in a process zone;
- (b) during a first process stage,
- (i) flowing a tungsten-containing gas and a first reduction agent into said deposition zone, and
- (ii) maintaining the deposition zone at process conditions suitable for depositing a first tungsten layer on said substrate;
- (c) during a second process stage after said first process stage, flowing a diborane gas into said deposition zone for between about 5-20 seconds without flowing a tungsten-containing gas into said deposition zone, and
- (d) during a third process stage after said second stage,
- (i) flowing a process gas comprising a tungsten-containing source, diborane and a second reduction agent into said deposition zone, and
- (ii) maintaining the deposition zone at process conditions suitable for depositing a second tungsten layer over said first layer.
A chemical vapor deposition process for depositing a tungsten film on a substrate, said process comprising:
- (a) placing a substrate in a deposition zone;
- (b) during a first process stage,
- (i) introducing a process gas comprising a tungsten-containing source and a first reduction agent into said deposition zone, and
- (ii) maintaining the deposition zone at process conditions suitable to deposit a first tungsten layer over said substrate;
- and
- (c) during a second process stage after said first stage,
- (i) introducing a process gas comprising a tungsten-containing source, a nitrogen-containing source, a group III or V hydride and a second reduction agent into said deposition zone, and
- (ii) maintaining the deposition zone at process conditions suitable for depositing a second tungsten layer over said first tungsten layer.
A chemical vapor deposition process for depositing a tungsten film on a substrate, said process comprising:
- (a) placing a substrate in a process zone;
- (b) during a first process stage,
- flowing a first process gas comprising WF.sub.6 and SiH.sub.4 into said deposition zone and maintaining the deposition zone at process conditions suitable for depositing a first tungsten layer on said substrate;
- (c) during a second process stage after said first process stage, stopping the flow of said first process gas and thereafter, flowing a diborane gas into said deposition zone for between about 5-20 seconds without flowing a tungsten-containing source into said deposition zone;
- and
- (d) during a third process stage after said second stage, flowing a second process gas comprising WF.sub.6, diborane and molecular hydrogen into said deposition zone and maintaining the deposition zone at process conditions suitable for depositing a second tungsten layer over said first layer.
Dependencies are inferred from the claim text.