Patent US4287074A successfully refreshed from Google Patents.
Patent US4816879A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4816879A Expired / Lapsed US ⏱️ 0.0 years remaining

Schottky-type rectifier having controllable barrier height

Assignee: Philips North America LLC
•
Filing: 1982-12-08
•
Granted: 1989-03-28
•
Expires: 2002-12-08
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A Schottky-type diode has a conductor-to-semiconductor barrier height φ B that is controlled by adjusting the thickness of a metal silicide layer (22) which forms a rectifying junction (20) with an N-type semiconductor (24). The silicide layer is constituted with two or more metals such as platinum and nickel.

Inventors

  • 👤 Russell C. Ellwanger

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 02:51
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/60; H10D64/64; H10D64/01; H10D64/012; H10D64/0121; H10D8/00; H10D8/60

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 208 words
A rectifier in which a semiconductor body has an N-type semiconductive region, a metal silicide layer adjoins the N-type region to define a rectifying junction at an interface therebetween, and a conductive non-silicide layer ohmically adjoins the silicide layer across from the junction, characterized in that : the silicide layer is sufficiently thin that the actual conductor-to-semiconductor barrier height φ B at the junction does not substantially equal the intrinsic conductor-to-semiconductor barrier height φ B0 at an interface between material which is the same as that of the N-type region along the junction and material which is the same as that of the silicide layer along the junction and has the same average composition as the silicide layer; the absolute value of (φ B0 -φB)/(φ Bo -φ BN ) is not less than 0.15 where φ BN is the conductor-to-semiconductor barrier height at an interface between material which is the same as that of the N-type region along the junction and material which is the same as that of the non-silicide layer; and the silicide layer comprises (1) a first layer adjoining the N-type region and (2) a second layer overlying the first layer across from the junction and having a different average composition than the first layer.
Claim 2
Dependent Claim 208 words
A rectifier in which a semiconductor body has an N-type semiconductive region, a metal silicide layer adjoins the N-type region to define a rectifying junction at an interface therebetween, and a conductive non-silicide layer ohmically adjoins the silicide layer across from the junction, characterized in that : the silicide layer is sufficiently thin that the actual conductor-to-semiconductor barrier height φ B at the junction does not substantially equal the intrinsic conductor-to-semiconductor barrier height φ B0 at an interface between material which is the same as that of the N-type region along the junction and material which is the same as that of the silicide layer along the junction and has the same average composition as the silicide layer; the absolute value of (φ B0 -φB)/(φ Bo -φ BN ) is not less than 0.15 where φ BN is the conductor-to-semiconductor barrier height at an interface between material which is the same as that of the N-type region along the junction and material which is the same as that of the non-silicide layer; and the silicide layer comprises (1) a first layer adjoining the N-type region and (2) a second layer overlying the first layer across from the junction and having a different average composition than the first layer.
Claim 3
Dependent Claim 55 words
A rectifier as in claim 1 characterized in that the average composition of the first layer is substantially Ni y Pt 1-y Si where Y is variable between 0 and 1 and that the average composition of the second layer is substantially Ni z Pt 1-Z Si where Z is variable between 0 and Y.
Claim 4
Dependent Claim 143 words
A rectifier in which a semiconductor body as an N-type semiconductive region, a metal silicide layer constituted with at least two selected metals adjoins the N-type region to define a rectifying junction at an interface therebetween, and a conductive non-silicide layer ohmically adjoins the silicide layer across from the junction, characterized in that the silicide layer is the remainder of an original metal silicide layer of greater thickness than the silicide layer which is sufficiently thin that the actual conductor-to-semiconductor barrier height φ B at the junction does not substantially equal the intrinsic conductor-to-semiconductor barrier height φ B0 at an interface between material which is the same as that of the N-type region along the junction and material which is the same as that of the original silicide layer along the junction and has the same average composition as the original silicide layer.
Claim 5
Dependent Claim 143 words
A rectifier in which a semiconductor body as an N-type semiconductive region, a metal silicide layer constituted with at least two selected metals adjoins the N-type region to define a rectifying junction at an interface therebetween, and a conductive non-silicide layer ohmically adjoins the silicide layer across from the junction, characterized in that the silicide layer is the remainder of an original metal silicide layer of greater thickness than the silicide layer which is sufficiently thin that the actual conductor-to-semiconductor barrier height φ B at the junction does not substantially equal the intrinsic conductor-to-semiconductor barrier height φ B0 at an interface between material which is the same as that of the N-type region along the junction and material which is the same as that of the original silicide layer along the junction and has the same average composition as the original silicide layer.
Claim 6
Dependent Claim 65 words
A rectifier as in claim 3 characterized in that the absolute value of (φ B0 -φ B )/(φ B0 -φ BN ) is not less than 0.15 where φ BN is the conductor-to-semiconduct barrier height at an interface between material which is the same as that of the N-type region along the junction and material which is the same as that of the non-silicide layer.
Claim 7
Dependent Claim 27 words
A rectifier as in claim 4 characterized in that a self-induced electric field penetrates through the entire thickness of the silicide layer and into the non-silicide layer.
Claim 8
Dependent Claim 42 words
A rectifier as in claim 4 characterized in that the silicide layer comprises a first layer adjoining the N-type region and a second layer overlying the first layer across from the junction and having a different average composition than the first layer.
Claim 9
Dependent Claim 55 words
A rectifier as in claim 6 characterized in that the average composition of the first layer is substantially Ni Y Pt 1-Y Si where Y is variable between 0 and 1 and that the average composition of the second layer is substantially Ni Z Pt 1-Z Si where Z is variable between 0 and Y.

References Cited (Backward Citations)

US3841904A Cited
US3906540A Cited
US4248688A Cited
US4492971A Cited
US4359486A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-03-27 1992-09-26 1993-03-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-03-27 1996-09-26 1997-03-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-03-27 2000-09-26 2001-03-28 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag