Patent US2338395A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4963506A Expired / Lapsed US ⏱️ 0.0 years remaining

Selective deposition of amorphous and polycrystalline silicon

Assignee: NXP USA Inc
•
Filing: 1989-04-24
•
Granted: 1990-10-16
•
Expires: 2009-04-24
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method for selectively depositing amorphous or polycrystalline silicon wherein a wafer having exposed silicon regions thereon is placed into a CVD reactor and subjected to a silicon containing gas and a halogen containing gas, at least one of which flows into the reactor with a hydrogen carrier gas. Amorphous silicon may be selectively deposited in the range of approximately 200 to 550 degrees centigrade while polycrystalline silicon may be selectively deposited in the range of approximately 550 to 750 degrees centigrade. It is also possible to deposit polycrystalline silicon at temperatures in the range of approximately 750 to 1000 degrees centigrade by employing another embodiment of the present invention.

Inventors

  • 👤 Hang M. Liaw
  • 👤 Christian A. Seelbach

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 22:56
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/20; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/24; H10P14/27; H10P14/271; Y; Y10; Y10S; Y10S148/00; Y10S148/025; Y10S148/026; Y10S148/122; Y10S148/169

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 59 words
A method for selectively depositing amorphous or polycrystalline silicon comprising the steps of: placing a wafer having exposed silicon regions thereon into a CVD reactor; and subjecting said wafer to gas mixture consisting essentially of a silicon containing gas and a halogen containing gas, at least one of said gases flowing into said reactor with a hydrogen carrier gas.
Claim 2
Independent Claim 59 words
A method for selectively depositing amorphous or polycrystalline silicon comprising the steps of: placing a wafer having exposed silicon regions thereon into a CVD reactor; and subjecting said wafer to gas mixture consisting essentially of a silicon containing gas and a halogen containing gas, at least one of said gases flowing into said reactor with a hydrogen carrier gas.
Claim 3
Dependent Claim 45 words
The method of claim 1 wherein the reactor temperature is in the range of approximately 200 to 550 degrees centigrade for the selective deposition of amorphous silicon and in the range of approximately 550 to 750 degrees centigrade for the selective deposition of polycrystalline silicon.
Claim 4
Dependent Claim 20 words
The method of claim 2 wherein the reactor pressure is in the range of approximately 100 millitorr to 100 torr.
Claim 5
Dependent Claim 20 words
The method of claim 3 wherein the silicon containing gas is a silane and halogen containing gas is hydrogen chloride.
Claim 6
Dependent Claim 24 words
The method of claim 4 wherein the gases flow into the reactor simultaneously, both gases flowing into said reactor with a hydrogen carrier gas.
Claim 7
Dependent Claim 48 words
The method of claim 1 wherein polycrystalline silicon is selectively deposited by the silicon containing gas and the halogen containing gas being derived from a single gas containing both silicon and a halogen, said silicon and halogen containing gas flowing into the reactor with a hydrogen carrier gas.
Claim 8
Dependent Claim 20 words
The method of claim 6 wherein the reactor temperature is in the range of approximately 750 to 1000 degrees centigrade.
Claim 9
Dependent Claim 33 words
The method of claim 7 wherein the silicon and halogen containing gas has a higher halogen content initially for seeding and a lower halogen content following seeding for the remainder of the deposition.
Claim 10
Dependent Claim 33 words
The method of claim 7 wherein the silicon and halogen containing gas maintains the same composition throughout deposition and the initial seeding occurs at a lower temperature than the remainder of the deposition.
Claim 11
Independent Claim 93 words
A method for selectively depositing amorphous or polycrystalline silicon comprising the steps of: placing a wafer having exposed silicon regions thereon into a CVD reactor; heating said rector to a temperature in the range of approximately 200 to 550 degrees centigrade for the selective deposition of amorphous silicon or in the range of approximately 550 to 750 degrees centigrade for the selective deposition of polycrystalline silicon; and subjecting said wafer to a silane and a halogen containing gas, at least one of said gases flowing into said reactor with a hydrogen carrier gas.
Claim 12
Independent Claim 93 words
A method for selectively depositing amorphous or polycrystalline silicon comprising the steps of: placing a wafer having exposed silicon regions thereon into a CVD reactor; heating said rector to a temperature in the range of approximately 200 to 550 degrees centigrade for the selective deposition of amorphous silicon or in the range of approximately 550 to 750 degrees centigrade for the selective deposition of polycrystalline silicon; and subjecting said wafer to a silane and a halogen containing gas, at least one of said gases flowing into said reactor with a hydrogen carrier gas.
Claim 13
Dependent Claim 20 words
The method of claim 10 wherein the reactor pressure is in the range of approximately 100 millitorr to 100 torr.
Claim 14
Dependent Claim 13 words
The method of claim 10 wherein the halogen containing gas is hydrogen chloride.
Claim 15
Dependent Claim 22 words
The method of claim 12 wherein the silane and the hydrogen chloride flow into the reactor simultaneously with a hydrogen carrier gas.
Claim 16
Independent Claim 86 words
A method for selectively depositing polycrystalline silicon comprising the steps of: placing a wafer having exposed silicon regions thereon into a CVD reactor; heating said reactor to a temperature in the range of approximately 750 to 1000 degrees centigrade; and subjecting said wafer to a gas including silicon and a halogen, said gas flowing into said reactor with a hydrogen carrier gas, said gas further having a higher halogen content initially for seeding and a lower halogen content following seeding for the remainder of the deposition.
Claim 17
Independent Claim 86 words
A method for selectively depositing polycrystalline silicon comprising the steps of: placing a wafer having exposed silicon regions thereon into a CVD reactor; heating said reactor to a temperature in the range of approximately 750 to 1000 degrees centigrade; and subjecting said wafer to a gas including silicon and a halogen, said gas flowing into said reactor with a hydrogen carrier gas, said gas further having a higher halogen content initially for seeding and a lower halogen content following seeding for the remainder of the deposition.
Claim 18
Dependent Claim 20 words
The method of claim 14 wherein the reactor pressure is in the range of approximately 100 millitorr to 100 torr.
Claim 19
Dependent Claim 20 words
The method of claim 14 wherein the gases employed are from the group comprising chlorosilane, dichlorosilane, trichlorosilane and silicon tetrachloride.
Claim 20
Independent Claim 89 words
A method for selectively depositing polycrystalline silicon comprising the steps of: placing a wafer having exposed silicon regions thereon into a CVD reactor; heating said reactor to a temperature of approximately 850 degrees centigrade and setting the reactor pressure at approximately 55 torr; subjecting said wafer to silicon tetrachloride gas flowing into said reactor with a hydrogen carrier gas at a hydrogen flow rate in the range of 15 to 32 liters/minute for approximately 5 minutes; and subjecting said wafer to a gas mixture of, dichlorosilane and hydrogen chloride.
Claim 21
Independent Claim 89 words
A method for selectively depositing polycrystalline silicon comprising the steps of: placing a wafer having exposed silicon regions thereon into a CVD reactor; heating said reactor to a temperature of approximately 850 degrees centigrade and setting the reactor pressure at approximately 55 torr; subjecting said wafer to silicon tetrachloride gas flowing into said reactor with a hydrogen carrier gas at a hydrogen flow rate in the range of 15 to 32 liters/minute for approximately 5 minutes; and subjecting said wafer to a gas mixture of, dichlorosilane and hydrogen chloride.
Claim 22
Independent Claim 86 words
A method for selectively depositing polycrystalline silicon comprising the steps of: placing a wafer having exposed silicon regions thereon into a CVD reactor; heating said reactor to a temperature in the range of approximately 750 to 1000 degrees centigrade; and subjecting said wafer to a gas including silicon and a halogen, said gas flowing into said reactor with a hydrogen carrier gas, said gas further maintaining the same composition throughout deposition and the initial seeding occurring at a lower temperature than the remainder of the deposition.
Claim 23
Independent Claim 86 words
A method for selectively depositing polycrystalline silicon comprising the steps of: placing a wafer having exposed silicon regions thereon into a CVD reactor; heating said reactor to a temperature in the range of approximately 750 to 1000 degrees centigrade; and subjecting said wafer to a gas including silicon and a halogen, said gas flowing into said reactor with a hydrogen carrier gas, said gas further maintaining the same composition throughout deposition and the initial seeding occurring at a lower temperature than the remainder of the deposition.
Claim 24
Dependent Claim 20 words
The method of claim 18 wherein the reactor pressure is in the range of approximately 100 millitorr to 100 torr.
Claim 25
Dependent Claim 21 words
The method of claim 18 wherein the gas employed is one of the group comprising chlorosilane, dichlorosilane, trichlorosilane and silicon tetrachloride.

References Cited (Backward Citations)

JPS5524459A Cited
US4497683A Cited
US4473598A Cited
US4547231A Cited
JPS60193324A Cited
JPS6189620A Cited
US4592792A Cited
JPS61174366A Cited
US4615762A Cited
US4786615A Cited
US4847214A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-10-15 1994-04-16 1994-10-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-10-15 1998-04-16 1998-10-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-10-15 2002-04-16 2002-10-16 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag