US4616408A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Inversely processed resistance heater
Assignee: HP Inc
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Filing: 1985-01-04
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Granted: 1986-10-14
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Expires: 2005-01-04
Abstract
Abstract A unique inverse processed film resistance heater structure is disclosed. A conventional passivation wear layer is deposited directly on a first substrate, followed by the deposition and patterning of resistive and conductive layers, and covered by an isolation layer and a thick support layer. The thick support layer is then bonded to a second substrate and the first substrate is removed so that a uniform, flat passivation layer is exposed. The result is a film resistor which has a reduced failure rate as compared to the prior art because it is covered by a passivation wear layer with fewer pin-holes and reduced stress.
Inventors
- 👤 William J. Lloyd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:12
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/315; B41J2/32; B41J2/335; B41J2/33505; B41J2/33535; B41J2/005; B41J2/01; B41J2/135; B41J2/14; B41J2/14016; B41J2/14088; B41J2/14112; B41J2/14129; B41J2/33545; B41J2/3355; B41J2/33555; B41J2/3357; B41J2/3359; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49083; Y10T29/49117; Y10T29/49124; Y10T29/49155
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
95 words
A method of fabricating a resistance heater on a first substrate, comprising in order the steps of: (1) depositing a first electrically non-conductive, uniformly thick passivation wear layer on the first substrate; (2) permanently depositing a resistor connected to a plurality of conductors on the first passivation layer; (3) depositing a support layer; and (4) removing the first substrate while leaving said first passivation layer to protect the resistor from externally applied stress and thereby exposing an outer surface of the first uniformly thick passivation layer overlaying the resistor, said outer surface being substantially flat.
Claim 2
Independent Claim
95 words
A method of fabricating a resistance heater on a first substrate, comprising in order the steps of: (1) depositing a first electrically non-conductive, uniformly thick passivation wear layer on the first substrate; (2) permanently depositing a resistor connected to a plurality of conductors on the first passivation layer; (3) depositing a support layer; and (4) removing the first substrate while leaving said first passivation layer to protect the resistor from externally applied stress and thereby exposing an outer surface of the first uniformly thick passivation layer overlaying the resistor, said outer surface being substantially flat.
Claim 3
Dependent Claim
18 words
A method as in claim 1 further comprising between steps (1) and (2) depositing a second passivation layer.
Claim 4
Dependent Claim
17 words
A method as in claim 1 further comprising between steps (2) and (3) depositing an isolation layer.
Claim 5
Dependent Claim
21 words
A method as in claim 1 further comprising between steps (3) and (4) bonding a second substrate to the support layer.
Claim 6
Dependent Claim
19 words
A method as in claim 1 further comprising after step (4) bonding a second substrate to the support layer.
Claim 7
Independent Claim
109 words
A method of fabricating a resistance heater on a first substrate, comprising in order the steps of: (1) depositing a first electrically non-conductive, uniformly thick passivation wear layer on the first substrate; (2) permanently depositing a resistive and conductive layer on the first passivation layer; (3) patterning the resistive and conductive layer to form a resistor connected to a plurality of conductors; (4) depositing a support layer; and (5) removing the first substrate while leaving said first passivation layer to protect the resistor from externally applied stress and thereby exposing an outer surface of the first uniformly thick passivation layer overlaying the resistor, said outer surface being substantially flat.
Claim 8
Independent Claim
109 words
A method of fabricating a resistance heater on a first substrate, comprising in order the steps of: (1) depositing a first electrically non-conductive, uniformly thick passivation wear layer on the first substrate; (2) permanently depositing a resistive and conductive layer on the first passivation layer; (3) patterning the resistive and conductive layer to form a resistor connected to a plurality of conductors; (4) depositing a support layer; and (5) removing the first substrate while leaving said first passivation layer to protect the resistor from externally applied stress and thereby exposing an outer surface of the first uniformly thick passivation layer overlaying the resistor, said outer surface being substantially flat.
Claim 9
Dependent Claim
18 words
A method as in claim 6 further comprising between steps (1) and (2) depositing a second passivation layer.
Claim 10
Dependent Claim
17 words
A method as in claim 6 further comprising between steps (3) and (4) depositing an isolation layer.
Claim 11
Dependent Claim
21 words
A method as in claim 6 further comprising between steps (4) and (5) bonding a second substrate to the support layer.
Claim 12
Dependent Claim
19 words
A method as in claim 6 further comprising after step (5) bonding a second substrate to the support layer.
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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) | 1989-10-13 | 1990-04-14 | 1990-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-10-13 | 1994-04-14 | 1994-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-10-13 | 1998-04-14 | 1998-10-14 | $7700.00 | Window Closed / Lapsed |