US5057446A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making an EEPROM with improved capacitive coupling between control gate and floating gate
Assignee: Texas Instruments Inc
•
Filing: 1990-08-06
•
Granted: 1991-10-15
•
Expires: 2010-08-06
Abstract
Abstract According to the invention, an integrated circuit with improved capacitive coupling is provided, and includes a first conductor (20), a second conductor (16), and a third conductor (22). The second conductor (22) and third conductor (16) are disposed adjacent each other, separated by an insulator region (60). The first conductor (20) contacts the third conductor (16) and extends across a portion of the third conductor (22). The first and third conductors are separated by an insulator region (54). A voltage applied to first conductor (20) and second conductor (16) is capacitively coupled to third conductor (22).
Inventors
- 👤 Manzur Gill
- 👤 David J. McElroy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 00:13
CPC Classifications
H; H10; H10B; H10B41/00; H10B41/30; H10D; H10D30/00; H10D30/60; H10D30/68; H10D30/681; H10D30/683; H10D64/00; H10D64/01; H10D64/031; H10D64/035
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
135 words
A method for fabricating an electrically erasable and programmable memory cell at a face of a semiconductor layer having a first conductivity type, comprising the steps of: selectively doping the semiconductor layer with a dopant of a second conductivity type opposite the first conductivity type to create a drain region and a source region spaced by a channel area; forming a first conductor layer over the face; selectively etching the first conductor layer to define a first control gate conductor; forming a second conductor layer insulatively over the face; selectively etching the second conducting layer to define a floating gate conductor, the floating gate conductor insulatively extending over the first control gate conductor; and forming a second control gate conductor insulatively adjacent the floating gate conductor and inc contact with said first control gate conductor.
Claim 2
Independent Claim
135 words
A method for fabricating an electrically erasable and programmable memory cell at a face of a semiconductor layer having a first conductivity type, comprising the steps of: selectively doping the semiconductor layer with a dopant of a second conductivity type opposite the first conductivity type to create a drain region and a source region spaced by a channel area; forming a first conductor layer over the face; selectively etching the first conductor layer to define a first control gate conductor; forming a second conductor layer insulatively over the face; selectively etching the second conducting layer to define a floating gate conductor, the floating gate conductor insulatively extending over the first control gate conductor; and forming a second control gate conductor insulatively adjacent the floating gate conductor and inc contact with said first control gate conductor.
Claim 3
Dependent Claim
43 words
The method of claim 1, in which the step of selectively etching the first conductor layer defines said first control gate conductor to insulatively extend over a first portion of said channel area, said first control gate conductor forming a merged pass gate.
Claim 4
Dependent Claim
32 words
The method of claim 2, in which the step of selectively etching the second conductor layer defines said floating gate conductor to insulatively extend over a second portion of said channel area.
Claim 5
Dependent Claim
40 words
The method of claim 1, in which the step of selectively etching the second conductor layer defines said floating gate conductor to insulatively extend over the entire length of said channel area between said source region and said drain region.
Claim 6
Dependent Claim
26 words
The method of claim 1, in which said first control gate conductor and said second control gate conductor fold around an end of said floating gate.
Claim 7
Dependent Claim
59 words
The method of claim 1, further comprising the steps of: forming a first insulator region over said source region; forming a second insulator region over said drain region; forming a first thick insulator region adjacent said source region remote from said channel area; and forming a second thick insulator region adjacent said drain region remote from said channel area.
Claim 8
Dependent Claim
46 words
The method of claim 6, in which the step of selectively etching the first conductor layer defines said first control gate conductor to extend over at least a portion of said second insulator region and over at least a portion of said second thick insulator region.
Claim 9
Dependent Claim
40 words
The method of claim 6, in which the step of selectively etching the second conductor layer defines said floating gate conductor to extend over said first insulator region and over at least a portion of said first thick insulator region.
References Cited (Backward Citations)
US4099196A
Cited
US4203158A
Cited
US4203158B1
Cited
US4180826A
Cited
US4377818A
Cited
US4258466A
Cited
US4281397A
Cited
US4301518A
Cited
US4493057A
Cited
US4377857A
Cited
JPS57112066A
Cited
US4668970A
Cited
US4686558A
Cited
EP0105802A2
Cited
US4590504A
Cited
US4608591A
Cited
WO1985001146A1
Cited
EP0144900A2
Cited
US4569117A
Cited
US4652897A
Cited
US4622737A
Cited
US4616245A
Cited
US4752912A
Cited
US4695979A
Cited
US4742492A
Cited
US4804637A
Cited
US4669177A
Cited
US4715014A
Cited
US4797372A
Cited
US4736342A
Cited
US4718041A
Cited
US4887142A
Cited
US4855800A
Cited
US4878096A
Cited
US4879254A
Cited
US4853895A
Cited
US4924437A
Cited
US4935791A
Cited
US4912676A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-10-14 | 1995-04-15 | 1995-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-10-14 | 1999-04-15 | 1999-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-10-14 | 2003-04-15 | 2003-10-15 | $7700.00 | Window Closed / Lapsed |