EP0192871A1
Expired / Lapsed
EP
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A method of forming a polysilicon resistor in a polycide line
Assignee: Thorn EMI North America Inc
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Filing: 1985-08-15
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Granted: —
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Expires: 2005-08-15
Abstract
Abstract A method of forming a polysilicon resistor in a polycide line comprises forming a layer of oxide (14) on a substrate (12) and then forming layer of polysilicon (16) over the oxide. A selected area (22) of the polysilicon (16) is doped to form a resisitive region (30) and then oxidised to establish a thick oxide layer (32) which forms a barrier for the resistive region (30). The polysilicon layer (16) external of the selected area (22) is then selectively doped. Subsequently a silicide layer (36) is formed over the entire structure and is then defined to form one or more polycide lines (40, 50) which project over or extend across the resistive region (30). The thick oxide layer (32) protects the resistive region (30) during the definition of the polycide lines. Subsequently the thick oxide (32) and the underlying resistive region (30) are etched to define a resistor within or between the polycide lines.
Inventors
- 👤 Ronald R. Bourassa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 22:54
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/40; H10D1/47; H10P; H10P95/00; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/064; H10W20/066
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
67 words
A method of forming a polysilicon resistor in a polycide line, comprising the steps of: locating a barrier material on top of a polysilicon region designated for location of a polysilicon resistor; then adding silicide over the polysilicon; and defining the silicide and the polysilicon to form a polysilicon resistor in contact with a polycide line, the resistor being separated from the silicide by said barrier material.
Claim 2
Independent Claim
67 words
A method of forming a polysilicon resistor in a polycide line, comprising the steps of: locating a barrier material on top of a polysilicon region designated for location of a polysilicon resistor; then adding silicide over the polysilicon; and defining the silicide and the polysilicon to form a polysilicon resistor in contact with a polycide line, the resistor being separated from the silicide by said barrier material.
Claim 3
Dependent Claim
30 words
A method as claimed in Claim 1, wherein before said barrier material is located on the polysilicon region, said designated polysilicon region is doped with impurities for a polysilicon resistor..
Claim 4
Dependent Claim
25 words
A method as claimed in Claim 1 or Claim 2, wherein said barrier material comprises an oxide developed on top of said designated polysilicon region.
Claim 5
Dependent Claim
30 words
A method as claimed in Claim 3 wherein said oxide is developed by oxidizing said designated polysilicon region, and wherein an oxidation-inhibiting layer is established outside said designated polysilicon region.
Claim 6
Independent Claim
27 words
A method as claimed in any preceding claim, wherein said barrier material is established on top of an area larger than and encompassing said designated resistor region.
Claim 7
Independent Claim
20 words
A method as claimed in any preceding claim, wherein both the polycide line and the polysilicon resistor are simultaneously defined.
Claim 8
Dependent Claim
37 words
A method as claimed in Claim 6, comprising the steps of locating a photoresist over the silicide and etching the silicide, the barrier material and the polysilicon to define both the polycide line and the polysilicon resistor.
Claim 9
Independent Claim
30 words
A method as claimed in any of Claims 1 to 5, wherein the polycide line is defined prior to defining the polysilicon into a resistor in the designated resistor region.
Claim 10
Dependent Claim
59 words
A method as claimed in Claim 8 comprising the steps of locating a photoresist over the silicide and in a line extending across said designated region but being discontinuous-over said designated region, and then etching through the silicide not covered by said photoresist down to said barrier material, and thereafter forming the polysilicon resistor from said designated resistor region.
Claim 11
Independent Claim
99 words
A method of forming a polysilicon resistor in a polycide line, comprising the steps of: resistor and polycide lines are to be formed with a layer of oxidation-inhibiting material; etching an opening through said oxidation-inhibiting layer to delineate a designated resistor region; implanting impurities into the polysilicon through said opening; establishing a relatively thick oxide in said opening on top of the polysilicon for preventing subsequently added silicide from contacting the-polysilicon in the designated resistor region; adding a layer of silicide covering the polysilicon and said oxide thereon; and defining a polysilicon line passing through the designated resistor area.
Claim 12
Independent Claim
99 words
A method of forming a polysilicon resistor in a polycide line, comprising the steps of: resistor and polycide lines are to be formed with a layer of oxidation-inhibiting material; etching an opening through said oxidation-inhibiting layer to delineate a designated resistor region; implanting impurities into the polysilicon through said opening; establishing a relatively thick oxide in said opening on top of the polysilicon for preventing subsequently added silicide from contacting the-polysilicon in the designated resistor region; adding a layer of silicide covering the polysilicon and said oxide thereon; and defining a polysilicon line passing through the designated resistor area.
Claim 13
Dependent Claim
15 words
A method as claimed in Claim 10, wherein said oxide is grown in said opening.
Claim 14
Dependent Claim
17 words
A method as claimed in Claim 10 or Claim 11, wherein said oxidation-inhibiting material is a nitride.
Claim 15
Independent Claim
16 words
A method as claimed in any of Claims 10 to 12, wherein said oxide is grown.
Claim 16
Independent Claim
25 words
A method as claimed in any of Claims 10 to 13, further comprising removing said oxidation-inhibiting layer prior to said step of adding a silicide.
References Cited (Backward Citations)
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