US4141136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of fabricating semiconductor devices with a low thermal resistance and devices obtained by the method
Assignee: Thales SA
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Filing: 1977-02-08
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Granted: 1979-02-27
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Expires: 1997-02-08
Abstract
Abstract A method of fabricating highly miniaturized semiconductor devices which must be electrically but not thermally insulated from ground, by replacing the conventional disk of beryllium oxide with a portion of the substrate itself so as to decrease the thermal resistance. To this end one starts with a disk of "PIN"-structure silicon. On one of its faces (P or N as the case may be) one deposits by epitaxy, or forms by successive diffusions, the active layers of the device and the surdoped zones. The "PIN" diode may be reverse biased if it is desired to create a capacity between active layers and metallic support serving as heat sink. Diodes and transistors in high-frequency microelectronics obtained by the method are also described.
Inventors
- 👤 Raymond Henry
- 👤 Philippe Morel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:29
CPC Classifications
H; H10; H10P; H10P54/00; H10W; H10W72/00; H10W72/30; H10W72/071; H10W72/073; H10W72/07331; H10W72/07337; H10W72/075; H10W72/07551; H10W72/07554; H10W72/50; H10W72/531; H10W72/536; H10W72/541; H10W72/547; H10W72/851; H10W72/874; H10W72/884; H10W90/00; H10W90/701; H10W90/731; H10W90/736
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
179 words
A method of fabricating semiconductor devices of the type including a semiconductor region constituting the active portion, the functioning of which leads to the dissipation of calories, a semiconductor substrate, and an electrically insulating support for the active portion intended to carry off the calories toward a heat sink by thermal conduction, the method comprising the following steps: providing a disk of high resistivity semiconductor material; creating, by diffusion or epitaxy, a pair of highly doped zones of mutually opposed types of conductivity respectively on the two large faces of the disk, leaving therebetween a layer of high resistivity semiconductor material with which the zones form a diode of the "PIN" type; epitaxially growing a semiconductor layer of the same conductivity type but less strongly doped than one of the zones, starting from the zone; selectively diffusing impurities into the semiconductor layer to produce a plurality of semiconductor devices; depositing a metallic film to facilitate connection of the devices to external circuits; separating the individual devices by cutting up the disks; and mounting each device on a heat-dissipating support.
Claim 2
Independent Claim
179 words
A method of fabricating semiconductor devices of the type including a semiconductor region constituting the active portion, the functioning of which leads to the dissipation of calories, a semiconductor substrate, and an electrically insulating support for the active portion intended to carry off the calories toward a heat sink by thermal conduction, the method comprising the following steps: providing a disk of high resistivity semiconductor material; creating, by diffusion or epitaxy, a pair of highly doped zones of mutually opposed types of conductivity respectively on the two large faces of the disk, leaving therebetween a layer of high resistivity semiconductor material with which the zones form a diode of the "PIN" type; epitaxially growing a semiconductor layer of the same conductivity type but less strongly doped than one of the zones, starting from the zone; selectively diffusing impurities into the semiconductor layer to produce a plurality of semiconductor devices; depositing a metallic film to facilitate connection of the devices to external circuits; separating the individual devices by cutting up the disks; and mounting each device on a heat-dissipating support.
Claim 3
Dependent Claim
18 words
The method recited in claim 1 including the step of incorporating means for reverse-biasing the "PIN" type diode.
Claim 4
Dependent Claim
43 words
The method recited in claim 1 wherein the growing step comprises epitaxially growing a semiconductor layer whose resistivity is greater than 4000 ohm-cm. and is of the same conductivity type but less strongly doped than one of the zones, starting from the zone.
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) | 1982-02-26 | 1982-08-28 | 1983-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-26 | 1986-08-28 | 1987-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-26 | 1990-08-28 | 1991-02-27 | $7700.00 | Window Closed / Lapsed |