US5358600A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making silicon quantum wires
Assignee: PAMERA MANAGEMENT Co LLC
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Filing: 1993-07-26
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Granted: 1994-10-25
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Expires: 2013-07-26
Abstract
Abstract A method of making semiconductor quantum wires employs a semiconductor wafer (14) as starting material. The wafer (14) is weakly doped p type with a shallow heavily doped p layer therein for current flow uniformity purposes. The wafer (14) is anodised in 20% aqueous hydrofluoric acid to produce a layer (5) microns thick with 70% porosity and good crystallinity. The layer is subsequently etched in concentrated hydrofluoric acid, which provides a slow etch rate. The etch increase porosity to a level in the region of 80% or above. At such a level, pores overlap and isolated quantum wires are expected to from with diameter less than or equal to 3 nm. The etched layer exhibits photoluminescence emission at photon energies well above the silicon bandgap (1.1 eV) and extending into the red region (1.6-2.0 eV) of the visible spectrum.
Inventors
- 👤 Leigh-Trevor Canham
- 👤 John M. Keen
- 👤 Weng Y. Leong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:22
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10H20/822; H10H20/826; H10H20/8264; B; B82; B82Y; B82Y10/00; H10P; H10P50/00; Y; Y10; Y10S; Y10S438/00; Y10S438/96; Y10S438/962
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
76 words
A method of producing luminescent silicon, said method comprising the steps of: providing a crystalline silicon substrate; anodizing at least a portion of said substrate to produce a porous layer of silicon at said portion of said substrate; and etching said porous layer so as to produce sufficient pore overlap with a porosity of between 60-90%, such that, when stimulated, said porous silicon emits light of a wavelength shorter than an emission wavelength of bulk silicon.
Claim 2
Independent Claim
76 words
A method of producing luminescent silicon, said method comprising the steps of: providing a crystalline silicon substrate; anodizing at least a portion of said substrate to produce a porous layer of silicon at said portion of said substrate; and etching said porous layer so as to produce sufficient pore overlap with a porosity of between 60-90%, such that, when stimulated, said porous silicon emits light of a wavelength shorter than an emission wavelength of bulk silicon.
Claim 3
Dependent Claim
29 words
A method of producing luminescent silicon according to claim 1, wherein said anodizing step takes place until said porous silicon has a pore width of less than 4 nm.
Claim 4
Dependent Claim
35 words
A method of producing luminescent silicon according to claim 2, wherein said etching step takes place until said porous silicon is comprised of silicon quantum wires having a thickness of not greater than 3 nm.
Claim 5
Dependent Claim
45 words
A method of producing luminescent silicon according to claim 1, wherein said etching step includes etching so as to provide sufficient pore overlap such that when irradiated with ultraviolet radiation, the porous silicon has a photoluminescence peak at an energy of at least 1.4 eV.
Claim 6
Dependent Claim
30 words
A method of producing luminescent silicon according to claim 1, wherein said anodizing step takes place until said porous silicon has more than 5×10 12 pores per cm 2 .
Claim 7
Independent Claim
60 words
A method of producing luminescence from crystalline silicon, said method comprising the steps of: processing crystalline silicon to form silicon quantum wires on at least a portion of said crystalline silicon, said quantum wires comprising a means for producing luminescence with an emission peak photon energy of at least 1.4 eV; and exciting said silicon quantum wires to produce luminescence.
Claim 8
Independent Claim
60 words
A method of producing luminescence from crystalline silicon, said method comprising the steps of: processing crystalline silicon to form silicon quantum wires on at least a portion of said crystalline silicon, said quantum wires comprising a means for producing luminescence with an emission peak photon energy of at least 1.4 eV; and exciting said silicon quantum wires to produce luminescence.
References Cited (Backward Citations)
US4987094A
Cited
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