US5081473A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature control transducer and MOS driver for thermal ink jet printing chips
Assignee: Xerox Corp
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Filing: 1990-07-26
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Granted: 1992-01-14
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Expires: 2010-07-26
Abstract
Abstract A transducer for a thermal ink jet printhead has a primary heating region having a tantalum layer, a silicon nitride layer and a polysilicon resistor layer. An n - drift layer resistor serves as a secondary heating region and a field layer of silicon dioxide acts as an insulator. The field layer is sandwiched between the primary heating region and the secondary heating region. The secondary heating region by heating the field layer causes the heat generated in the primary heating region to be directed toward ink which lies above the primary heating region. An electrical contact connects the polysilicon resistor layer of the primary heating region to a driving transistor located on the same silicon wafer as the transducer. The driving transistor has a field oxide layer sandwiched between an n - drift layer and a field plate layer, the field plate layer causing secondary pinch off of the n - drift layer thus enabling higher operating voltages.
Inventors
- 👤 William G. Hawkins
- 👤 Cathie J. Burke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:12
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/135; B41J2/16; B41J2/1621; B41J2/1626; B41J2/1601; B41J2/164; B41J2/1642; B41J2/1646; H; H10; H10D; H10D88/00; B41J2202/00; B41J2202/01; B41J2202/13
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
96 words
A transducer device for converting electrical energy to thermal energy and for directing the thermal energy to an object to be heated, comprising: a transducer field oxide layer; a primary heating region located on one side of the transducer field oxide layer for dissipating thermal energy toward the object; and a secondary heating region located on an opposite side of the transducer field oxide layer from the primary heating region, the secondary heating region dissipating thermal energy to the transducer field oxide layer to enable close temperature control of the primary heating region and the object.
Claim 2
Dependent Claim
96 words
A transducer device for converting electrical energy to thermal energy and for directing the thermal energy to an object to be heated, comprising: a transducer field oxide layer; a primary heating region located on one side of the transducer field oxide layer for dissipating thermal energy toward the object; and a secondary heating region located on an opposite side of the transducer field oxide layer from the primary heating region, the secondary heating region dissipating thermal energy to the transducer field oxide layer to enable close temperature control of the primary heating region and the object.
Claim 3
Dependent Claim
25 words
A device according to claim 1, further comprising: means for selectively applying an electrical current to said primary heating region and said secondary heating region.
Claim 4
Dependent Claim
45 words
A device according to claim 1, wherein: said primary heating region comprises a polysilicon resistor layer contacting said field oxide layer, a silicon nitride layer contacting said polysilicon resistor layer, and a tantalum layer contacting said silicon nitride layer and the object to be heated.
Claim 5
Dependent Claim
17 words
A device according to claim 1, wherein: said secondary heating region is an n - drift layer.
Claim 6
Dependent Claim
32 words
A device according to claim 3, wherein: said secondary heating region is an n - drift layer of phosphorous doped silicon having a dopant concentration of about 2×10 16 ions/cm 3 .
Claim 7
Dependent Claim
25 words
A device according to claim 2, wherein said means for applying comprises a common bus line connected to both said primary and secondary heating regions.
Claim 8
Dependent Claim
22 words
A device according to claim 5, wherein said n - drift layer of phosphorous doped silicon is formed in a silicon wafer.
Claim 9
Dependent Claim
38 words
A device according to claim 7, further comprising a driver transistor device constructed in said silicon wafer and wherein the drain of the driver device is in electrical contact with said polysilicon resistor layer of said transducer device.
Claim 10
Dependent Claim
11 words
A device according to claim 1, wherein the object is ink.
Claim 11
Dependent Claim
24 words
A device according to claim 9, wherein the transducer is operatively associated with an ink flow channel thereby producing a thermal ink jet transducer.
Claim 12
Dependent Claim
53 words
A driver device according to claim 10, further comprising: a driver field layer; and an n - drift layer on one side of said field oxide layer, and a field plate layer, on an opposite side of said driver field oxide layer, for causing secondary pinch off of the n - drift layer.
Claim 13
Dependent Claim
17 words
A driver device according to claim 10, wherein said field plate layer is a layer of polysilicon.
Claim 14
Dependent Claim
52 words
A driver device for a transducer comprising: a field oxide layer; an n - drift layer on one side of said field oxide layer; and means for causing secondary pinch off of said n - drift layer, said means for causing being connected to an opposite side of said field oxide layer.
Claim 15
Dependent Claim
52 words
A driver device for a transducer comprising: a field oxide layer; an n - drift layer on one side of said field oxide layer; and means for causing secondary pinch off of said n - drift layer, said means for causing being connected to an opposite side of said field oxide layer.
Claim 16
Dependent Claim
19 words
A device according to claim 13, wherein: said n - drift layer is a layer of phosphorous doped silicon.
Claim 17
Dependent Claim
16 words
A device according to claim 14, wherein said field oxide layer is a silicon dioxide layer.
Claim 18
Dependent Claim
17 words
A device according to claim 13, wherein said causing means comprises a layer of phosphorous doped polysilicon.
Claim 19
Dependent Claim
17 words
A device according to claim 13, further comprising: a gate layer surrounded by said field oxide layer.
Claim 20
Dependent Claim
14 words
A device according to claim 17, wherein: said gate layer is phosphorous doped silicon.
Claim 21
Dependent Claim
24 words
A device according to claim 18, wherein said gate layer of phosphorous doped silicon has a dopant concentration of 10 20 ions/cm 3 .
Claim 22
Dependent Claim
27 words
A device according to claim 13, wherein said causing means comprises a layer of phosphorous doped silicon having a dopant concentration of 10 20 ions/cm 3 .
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-01-13 | 1995-07-15 | 1996-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-01-13 | 1999-07-15 | 2000-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-01-13 | 2003-07-15 | 2004-01-14 | $7700.00 | Window Closed / Lapsed |