US5281841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
ESD protection element for CMOS integrated circuit
Assignee: US Philips Corp
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Filing: 1992-08-21
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Granted: 1994-01-25
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Expires: 2012-08-21
Abstract
Abstract A semiconductor device (1) includes a circuit having at least one transistor Tr1 and first and second electrodes (30) and (32). A protection element (20) having a device region (21) forming a pn junction (23) within the semiconductor body (10) and covered by an electrode layer (21c) is connected via an electrode (27) to one (30) of the first and second electrodes for providing a conductive path between the first and second electrodes (30) and (32) when a voltage above a threshold voltage is applied to the first electrode (30). The electrode layer (21c) forms with at least part (21a) of the device region (21) a potential barrier (B) for causing the conductive path provided by the protection element (20) to pass from the electrode (27) to the pn junction (23) at least partly via the device region (21) of the protection element (20) thereby increasing the resistance of the path to the pn junction (23).
Inventors
- 👤 Leonardus J. Van Roozendaal
- 👤 Rene G. M. Penning De Vries
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 05:19
CPC Classifications
H; H10; H10D; H10D89/00; H10D89/60; H10D89/601
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
128 words
A semiconductor device comprising a semiconductor body having device regions defining at least one transistor with first and second electrodes and a protection element having a device region forming a pn junction within the semiconductor body and covered by an electrode layer connected via an electrode to one of the first and second electrodes for providing a conductive path between the first and second electrodes when a voltage above a threshold voltage is applied to the first electrode, wherein the electrode layer forms with at least part of the device region of the protection element a potential barrier for causing the conductive path provided by the protection element to pass from the electrode to the pn junction at least partly via the device region of the protection element.
Claim 2
Dependent Claim
128 words
A semiconductor device comprising a semiconductor body having device regions defining at least one transistor with first and second electrodes and a protection element having a device region forming a pn junction within the semiconductor body and covered by an electrode layer connected via an electrode to one of the first and second electrodes for providing a conductive path between the first and second electrodes when a voltage above a threshold voltage is applied to the first electrode, wherein the electrode layer forms with at least part of the device region of the protection element a potential barrier for causing the conductive path provided by the protection element to pass from the electrode to the pn junction at least partly via the device region of the protection element.
Claim 3
Dependent Claim
49 words
A semiconductor device according to claim 1, further characterized in that the device region of the protection element comprises a first relatively highly doped subsidiary region forming an ohmic contact with the electrode layer and a relatively lowly doped subsidiary region forming the potential barrier with the electrode layer.
Claim 4
Dependent Claim
27 words
A semiconductor device according to claim 2, further characterized in that the first relatively highly doped subsidiary region is provided within the relatively lowly doped subsidiary region.
Claim 5
Dependent Claim
25 words
A semiconductor device according to claim 3, further characterized in that the first relatively highly doped subsidiary region is at least partly bounded by oxide.
Claim 6
Dependent Claim
40 words
A semiconductor device according to claim 2, further characterized in that the device region of the protection element further comprises a relatively lowly doped well region deeper than the relatively lowly doped subsidiary region which extends beyond the well region.
Claim 7
Dependent Claim
44 words
A semiconductor device according to claim 2, further characterized in that a second relatively highly doped subsidiary region forming an ohmic contact with the electrode layer is provided within the relatively lowly doped subsidiary region spaced from the first relatively highly doped subsidiary region.
Claim 8
Dependent Claim
23 words
A semiconductor device according to claim 1, further characterized in that the potential barrier formed by the electrode layer comprises a Schottky barrier.
Claim 9
Dependent Claim
19 words
A semiconductor device according to claim 1, further characterized in that the electrode layer comprises a metal silicide layer.
Claim 10
Dependent Claim
26 words
A semiconductor device according to claim 8, further characterized in that at least one device region of the transistor is covered by a metal silicide layer.
Claim 11
Dependent Claim
36 words
A semiconductor device according to claim 1, further characterized in that the protection element comprises an insulated gate field effect transistor with the device region forming the drain region of the insulated gate field effect transistor.
Claim 12
Dependent Claim
39 words
A semiconductor device according to claim 10, further characterized in that the insulated gate field effect transistor has a source region covered with an electrode layer which forms a potential barrier with at least part of the source region.
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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) | 1997-01-24 | 1997-07-26 | 1998-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-01-24 | 2001-07-26 | 2002-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-01-24 | 2005-07-26 | 2006-01-25 | $7700.00 | Window Closed / Lapsed |