EP0165547A2
Expired / Lapsed
EP
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A method of forming a shallow doped region in a semiconductor substrate
Assignee: International Business Machines Corp
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Filing: 1985-06-13
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Granted: —
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Expires: 2005-06-13
Abstract
Abstract A shallow (not more than about 30nm deep) doped region (24) is formed in a semiconductor substrate (10) by depositing at least two overlayers (12,14) on the top surface of the semiconductor substrate, one (14) of the overlayers containing metal atoms. The overlayers are such that a metal compound is formed from the metal atoms in one (14) of the overlayers and atoms from another one (12) of the overlayers when the multilayered structure is annealed at a temperature less than 700°C. At least one (12) of the overlayers contains atoms to be introduced as a dopant into the substrate. When the multilayer structure is annealed at a temperature less than 700°C the metal compound is formed and releases the atoms to be introduced into the substrate. This produces an interface (18) which moves towards the substrate and pushes the released atoms by the snowplow effect towards the substrate. The annealing is continued for a time sufficient to move the interface (18) to the top surface of the substrate to push the released atoms into the body of the substrate.
Inventors
- 👤 Gary Wayne Rubloff
- 👤 Marc Francis Wittmer
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 12:54
CPC Classifications
H; H10; H10P; H10P32/00; H10P32/10; H10P32/14; H10P32/1408; H10D; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0112; H10P32/1414; H10P32/17; H10P32/171
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
195 words
A method of forming a shallow doped region (22) in a semiconductor substrate (10), comprising the steps of: forming a multilayered structure by depositing at least two overlayers (12, 14) on the top surface of the semiconductor substrate (10), one (14) of the overlayers containing metal_atoms, the overlayers being such that a metal compound is formed from said metal atoms and atoms from another one (12) of the overlayers when the multilayered structure is annealed at a temperature less than 700°C, and at least one (12) of the overlayers containing atoms to be introduced as a dopant into the substrate; and annealing the multilayer structure at a temperature less than 700°C to form said metal compound, the formation of said metal compound releasing the atoms to be introduced into the substrate and producing an interface (18) which moves towards the substrate and pushes the released atoms by the snowplow effect towards the substrate, the annealing being performed for a time sufficient to move said interface to the top surface of the substrate to push the released atoms into the body of the substrate a distance not exceeding 30nm from the top surface of the substrate.
Claim 2
Independent Claim
195 words
A method of forming a shallow doped region (22) in a semiconductor substrate (10), comprising the steps of: forming a multilayered structure by depositing at least two overlayers (12, 14) on the top surface of the semiconductor substrate (10), one (14) of the overlayers containing metal_atoms, the overlayers being such that a metal compound is formed from said metal atoms and atoms from another one (12) of the overlayers when the multilayered structure is annealed at a temperature less than 700°C, and at least one (12) of the overlayers containing atoms to be introduced as a dopant into the substrate; and annealing the multilayer structure at a temperature less than 700°C to form said metal compound, the formation of said metal compound releasing the atoms to be introduced into the substrate and producing an interface (18) which moves towards the substrate and pushes the released atoms by the snowplow effect towards the substrate, the annealing being performed for a time sufficient to move said interface to the top surface of the substrate to push the released atoms into the body of the substrate a distance not exceeding 30nm from the top surface of the substrate.
Claim 3
Dependent Claim
58 words
A method as claimed in claim 1, in which the overlayers are such that a compound is formed from said metal atoms and atoms of another element present in the overlayers when the overlayers are annealed at a temperature less than 500°C, and the multilayer structure is annealed at a temperature less than 500°C to form said compound.
Claim 4
Dependent Claim
40 words
A method as claimed in claim 1 or claim 2, in which only two overlayers are deposited on the top surface of the substrate, the inner layer being comprised of a semiconductor material and the outer layer of a metal.
Claim 5
Dependent Claim
52 words
A method as claimed in claim 3, in which the inner layer is comprised of polycrystalline or amorphous silicon, doped with the atoms to be introduced as a dopant into the substrate, and the outer layer is comprised of a metal which forms a silicide upon the annealing of the multilayer structure.
Claim 6
Dependent Claim
29 words
A method as claimed in claim 4, in which the thickness of the outer layer is such that all the inner layer is consumed during formation of the silicide.
Claim 7
Dependent Claim
15 words
A method as claimed in claim 3, in which the inner layer consists of germanium.
Claim 8
Dependent Claim
19 words
A method as claimed in claim 3, in which the inner layer consists of GaAs, InP, CdTe or ZnSe.
Claim 9
Independent Claim
29 words
A method as claimed in any of claims 4 to 7, in which the metal-atom containing overlayer consists of Pd, Pt, Ni, Rh, Os, Ir, Cr, Co or Ru.
Claim 10
Dependent Claim
25 words
A method as claimed in claim 3, in which the outer, metal layer contains the atoms to be introduced as a dopant into the substrate.
Claim 11
Dependent Claim
70 words
A method as claimed in claim 1 or claim 2, in which the dopant atoms to be introduced into the substrate are a constituent of a compound which one of the overlayers is made of, and in which the formation of said metal compound from atoms present in the overlayers releases the atoms to be introduced into the substrate from the compound of which one of the overlayers is made.
Claim 12
Dependent Claim
27 words
A method as claimed in claim 10, in which the compound of which one of the overlayers is made is a Group III-V or Group II-VI compound.
Claim 13
Independent Claim
18 words
A method as claimed in any preceding claim, in which the substrate is a single crystal silicon layer.
Claim 14
Independent Claim
28 words
A method as claimed in any preceding claim, in which the atoms to be introduced as a dopant into the substrate are B, P, As or Sb atoms.
Claim 15
Independent Claim
21 words
A method as claimed in any preceding claim, including removing the overlayers from the substrate when the annealing has been completed.
References Cited (Backward Citations)
No citation records indexed.
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