Patent US3885243A successfully refreshed from Google Patents.
US3885243A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device
Assignee: BBC Brown Boveri AG Switzerland
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Filing: 1973-09-24
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Granted: 1975-05-20
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Expires: 1993-09-24
Abstract
Abstract Two or more semiconductor device connected in series opposition and contacted by pressure contacts are enclosed in a common housing to form a surge diverter. The two diodes connected in series opposition are formed from a single semiconductor wafer exhibiting three layers whose conductivity types alternate from one to the next. The end faces of the semiconductor wafers have an edge concentration of at least 1019 atoms/cm3, preferable 5.1020 atoms/cm3. The doping gradient is chosen so that the charge carrier concentration at a depth of 35 microns is still 1016 atoms/cm3. Different embodiments of the semiconductor device and housing structure are also disclosed.
Inventors
- 👤 Erich Weisshaar
- 👤 Dieter Spickenbreuther
- 👤 Bernd Sitte
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:40
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/10; H10D62/102; H10D62/103; H10D62/104; H10D99/00; H10W; H10W40/00; H10W40/60; H10W40/611; H10W72/00; H10W74/00; H10W74/10; H10W74/131; H10W74/141; H10W90/00; H10W40/20; H10W40/231; H10W40/235; H10W40/625
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
217 words
A semiconductor device comprising: a pair of semiconductor diodes connected in series opposition, said diodes formed in a single monocrystalline silicon semiconductor wafer having three layers of alternating conductivity types including an inner layer and a pair of outer layers, said semiconductor wafer bevelled around its periphery on both sides thereof, and having non-metalized end surfaces, wherein said end surfaces of said semiconductor wafer have an edge doping concentration of at least 1019 atoms/cm3, said wafer has a doping gradient at its end surfaces such that the doping concentration at a depth of 35 microns is greater than 1016 atoms/cm3, the doping concentration of said inner layer is less than 1017 atoms/cm3, preferably less than 1016 atoms/cm3, and the thickness of said outer layers of said semiconductor device is less than 100 microns; a pressure contact structurE juxtaposed to each face of said semiconductor wafer, each pressure contact structure including a thin, dish-shaped element of a highly ductile and highly conductive metal one side of which engages one of said nonmetalized end surfaces of said semiconductor wafer, and a thicker, disk-shaped conductive element abutting the exposed side of each dish-shaped element; and, a band of flexible insulative material surrounding the periphery of said semiconductor wafer, said insulative material adhering said thin, dish-shaped elements to said semiconductor wafer.
Claim 2
Dependent Claim
217 words
A semiconductor device comprising: a pair of semiconductor diodes connected in series opposition, said diodes formed in a single monocrystalline silicon semiconductor wafer having three layers of alternating conductivity types including an inner layer and a pair of outer layers, said semiconductor wafer bevelled around its periphery on both sides thereof, and having non-metalized end surfaces, wherein said end surfaces of said semiconductor wafer have an edge doping concentration of at least 1019 atoms/cm3, said wafer has a doping gradient at its end surfaces such that the doping concentration at a depth of 35 microns is greater than 1016 atoms/cm3, the doping concentration of said inner layer is less than 1017 atoms/cm3, preferably less than 1016 atoms/cm3, and the thickness of said outer layers of said semiconductor device is less than 100 microns; a pressure contact structurE juxtaposed to each face of said semiconductor wafer, each pressure contact structure including a thin, dish-shaped element of a highly ductile and highly conductive metal one side of which engages one of said nonmetalized end surfaces of said semiconductor wafer, and a thicker, disk-shaped conductive element abutting the exposed side of each dish-shaped element; and, a band of flexible insulative material surrounding the periphery of said semiconductor wafer, said insulative material adhering said thin, dish-shaped elements to said semiconductor wafer.
Claim 3
Dependent Claim
26 words
A semiconductor device as in claim 1, wherein the end faces of the semiconductor wafer have an edge concentration equal substantially to 5 . 1020 atoms/cm3.
Claim 4
Dependent Claim
27 words
A device as in claim 1, wherein the end faces of the semiconductor wafer have an edge concentration of between 1019 atoms/cm3 and 5 . 1020 atoms/cm3.
Claim 5
Dependent Claim
40 words
A device as in claim 1, wherein said pressure contact elements have end faces disposed toward the semiconductor wafer and in pressure contact therewith, said pressure contact element having the same geometric form and bearing symmetrically against said semiconductor wafer.
Claim 6
Dependent Claim
23 words
A device as in claim 1, wherein the inner layer of said semiconductor wafer at least 1.5 times the optimal thickness for thyristors.
Claim 7
Dependent Claim
16 words
A device as in claim 1, wherein said flexible insulative material is composed of silicone rubber.
Claim 8
Dependent Claim
183 words
A semiconductor voltage limiter device comprising: a pair of semiconductor diodes connected in series opposition, said diodes formed in a single semiconductor wafer having three layers of alternating conductivity types including an inner layer and a pair of outer layers, bevelled edges on both sides thereof and no metalization on the active surfaces thereof, wherein the end faces of said semiconductor wafer have an edge doping concentration of at least 1019 atoms/cm3, said wafer has a doping gradient at its end surfaces such that the doping concentration at a depth of 35 microns is greater than 1016 atoms/cm3, the doping concentration of said inner layer is less than 1017 atoms/cm3, preferably less than 1016 atoms/cm3, and said outer layers of said semiconductor wafer are less than 100 microns thick; solderless pressure contact assemblies engaging said non-metalized active surfaces of said semiconductor wafer, a housing for said semiconductor wafer and said solderless pressure contact assemblies; and, spring means engaging said housing for biasing said pressure contact assemblies into firm engagement with said semiconductor wafers, said housing applying a compressive force to said spring means.
Claim 9
Dependent Claim
183 words
A semiconductor voltage limiter device comprising: a pair of semiconductor diodes connected in series opposition, said diodes formed in a single semiconductor wafer having three layers of alternating conductivity types including an inner layer and a pair of outer layers, bevelled edges on both sides thereof and no metalization on the active surfaces thereof, wherein the end faces of said semiconductor wafer have an edge doping concentration of at least 1019 atoms/cm3, said wafer has a doping gradient at its end surfaces such that the doping concentration at a depth of 35 microns is greater than 1016 atoms/cm3, the doping concentration of said inner layer is less than 1017 atoms/cm3, preferably less than 1016 atoms/cm3, and said outer layers of said semiconductor wafer are less than 100 microns thick; solderless pressure contact assemblies engaging said non-metalized active surfaces of said semiconductor wafer, a housing for said semiconductor wafer and said solderless pressure contact assemblies; and, spring means engaging said housing for biasing said pressure contact assemblies into firm engagement with said semiconductor wafers, said housing applying a compressive force to said spring means.
Claim 10
Dependent Claim
46 words
A device as in claim 7, wherein said solderless pressure contact assemblies each include: thin dish-shaped elements formed of highly conductive and ductile metal, said dish-shaped elements directly contacting said semiconductor wafer; and, thicker disk-shaped conductive elements engaging the exposed dished surfaces of said dish-shaped elements.
Claim 11
Dependent Claim
60 words
A device as in claim 7, wherein said housing comprises: a bottom contact fixed to said housing for engaging one of said pressure contacts, a movable intermediate contact contained within said housing for engaging the other one of said pressure contacts; and, a cover assembly for sealing said housing and for applying pressure to said contacts contained within said housing.
Claim 12
Dependent Claim
21 words
A device as in claim 7, wherein: one of said solderless pressure contact assemblies includes a bottom portion of said housing.
Claim 13
Dependent Claim
26 words
A device as in claim 10, further comprising: a cooling assembly secured to said bottom portion of said housing for dissipating heat generated within said housing.
Claim 14
Dependent Claim
58 words
A device as in claim 7, wherein: one of said solderless pressure contact assemblies includes a disk-shaped conductive body, one surface of which engageS said semiconductor wafer; a reduced neck portion formed integral with another surface of said disk-shaped conductive body; and, wherein said spring means includes at least one spring washer positioned about said reduced neck portion.
Claim 15
Dependent Claim
31 words
A device as in claim 12, wherein: said housing includes a top portion for enclosing one end of said housing and for engaging and applying compressive pressure to said spring washer.
Claim 16
Dependent Claim
60 words
A device as in claim 7, wherein each of said solderless pressure contact assemblies includes a thin, dish-shaped element of a highly ductile and highly conductive metal one side of which engages said semiconductor wafer; a first disk-shaped conductive element abutting the exposed side of said dish-shaped element; and, a second disk-shaped conductive element abutting said first disk-shaped conductive element.
Claim 17
Dependent Claim
49 words
A device as in claim 7, wherein: said housing includes a ceramic sleeve, a pair of alloy ring elements rigidly secured to opposite ends of said ceramic sleeve; and, conductive top and bottom portions secured to said alloy ring elements for sealing said housing in a fluid tight manner.
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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) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |