US4704783A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for passivating the back channel of amorphous silicon field effect transistors
Assignee: General Electric Co
•
Filing: 1986-05-05
•
Granted: 1987-11-10
•
Expires: 2006-05-05
Abstract
Abstract An organic or inorganic base solution is employed as a means for passivating the back channel region of an amorphous silicon FET device following plasma etching of the back channel region. The passivation provided significantly reduces back channel leakage currents resulting in FET devices which are compatible with conventional processing methods and which exhibit desirable properties for use in liquid crystal display systems.
Inventors
- 👤 George E. Possin
- 👤 Harold G. Parks
- 👤 William W. Piper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:04
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10D84/0128; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/694; H10P14/6943; H10P14/69433; H10D30/00; H10D30/60; H10D30/67; H10D30/6729; H10D30/673; H10D30/6732; H10D30/674; H10D30/6741; H10D30/6743; H10D30/6746; H10P14/40; H10P14/416; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6334; H10P14/6336; H10P14/65; H10P14/6516; H10P14/6548; H10P50/00; H10P50/20; H10P50/24; H10P50/242; H10W; H10W74/00; H10W74/01; Y; Y10; Y10S; Y10S438/00; Y10S438/906; Y10S438/958
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
77 words
A method for passivating the back channel region of amorphous silicon field effect transistors, said method comprising the following ordered sequence of process steps: sputter etching doped amorphous silicon material at the bottom of a gap in an overlying metal layer; plasma etching said doped amorphous silicon material and a portion of an underlying amorphous silicon layer; exposing said amorphous silicon surface to a basic solution; and depositing a passivating dielectric layer over said field effect transistor.
Claim 2
Independent Claim
77 words
A method for passivating the back channel region of amorphous silicon field effect transistors, said method comprising the following ordered sequence of process steps: sputter etching doped amorphous silicon material at the bottom of a gap in an overlying metal layer; plasma etching said doped amorphous silicon material and a portion of an underlying amorphous silicon layer; exposing said amorphous silicon surface to a basic solution; and depositing a passivating dielectric layer over said field effect transistor.
Claim 3
Dependent Claim
15 words
The method of claim 1 in which said sputter etching occurs in an argon atmosphere.
Claim 4
Dependent Claim
17 words
The method of claim 1 in which said plasma etching is performed in a barrel plasma etcher.
Claim 5
Dependent Claim
13 words
The method of claim 1 in which said base comprises an inorganic base.
Claim 6
Dependent Claim
13 words
The method of claim 1 in which said base comprises an organic base.
Claim 7
Dependent Claim
14 words
The method of claim 5 in which said organic base comprises a monoethanolamine solution.
Claim 8
Dependent Claim
28 words
The method of claim 1 further including immediately subsequent to exposure to said basic solution, the steps of: rinsing said FET in distilled water and heating in air.
Claim 9
Dependent Claim
23 words
The method of claim 7 in which said heating in air occurs at a temperature of approximately 250° C. for approximately 15 minutes.
Claim 10
Dependent Claim
19 words
The method of claim 1 in which said passivating layer comprises silicon nitride deposited by plasma chemical vapor deposition.
Claim 11
Dependent Claim
19 words
The method of claim 9 in which said passivating layer is deposited at a temperature of approximately 150° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-11-09 | 1991-05-11 | 1991-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-09 | 1995-05-11 | 1995-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-09 | 1999-05-11 | 1999-11-10 | $7700.00 | Window Closed / Lapsed |