US5329141A
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Light emitting diode
Assignee: Sharp Corp
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Filing: 1992-10-30
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Granted: 1994-07-12
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Expires: 2012-10-30
Abstract
Abstract A light emitting diode of silicon carbide having a p-n junction comprising an n-type layer doped with donor impurities, a first p-type layer doped with acceptor impurities, and a second p-type layer doped with acceptor impurities and donor impurities. The first p-type layer has a thickness less than the diffusion length of electrons having flowed from the n-type layer. In this way, the first p-type layer effects light emission related to the acceptor impurities which recombine with the electrons having flowed from the n-type layer, and the second p-type layer effects light emission by donor-acceptor pairs which recombine with the electrons having flowed from the n-type layer.
Inventors
- 👤 Akira Suzuki
- 👤 Yoshihisa Fujii
- 👤 Hajime Saito
- 👤 Katsuki Furukawa
- 👤 Yoshimitsu Tajima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:37
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10H20/822; H10H20/826; H10H20/01; H10H20/011; H10H20/014
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
144 words
A light emitting diode of silicon carbide having a p-n junction, comprising: an n-type layer of silicon carbide doped with donor impurities; a first p-type layer of silicon carbide formed on the n-type layer, said first p-type layer being doped with acceptor impurities; and a second p-type layer of silicon carbide formed on the first p-type layer, said second p-type layer being doped with acceptor impurities and donor impurities; wherein said first p-type layer has a thickness less than the diffusion length of electrons having flowed from said n-type layer under a forward bias condition, so that said first p-type layer effects light emission related to the acceptor impurities caused by recombination with the electrons having flowed from said n-type layer, and said second p-type layer effects light emission by donor-acceptor pairs caused by recombination with the electrons having flowed from said n-type layer.
Claim 2
Dependent Claim
144 words
A light emitting diode of silicon carbide having a p-n junction, comprising: an n-type layer of silicon carbide doped with donor impurities; a first p-type layer of silicon carbide formed on the n-type layer, said first p-type layer being doped with acceptor impurities; and a second p-type layer of silicon carbide formed on the first p-type layer, said second p-type layer being doped with acceptor impurities and donor impurities; wherein said first p-type layer has a thickness less than the diffusion length of electrons having flowed from said n-type layer under a forward bias condition, so that said first p-type layer effects light emission related to the acceptor impurities caused by recombination with the electrons having flowed from said n-type layer, and said second p-type layer effects light emission by donor-acceptor pairs caused by recombination with the electrons having flowed from said n-type layer.
Claim 3
Dependent Claim
39 words
A light emitting diode according to claim 1, wherein a third p-type layer is formed on said second p-type layer, said third p-type layer having a higher hole concentration than said first p-type layer and said second p-type layer.
Claim 4
Dependent Claim
25 words
A light emitting diode according to claim 1, wherein the thickness of said first p-type layer is within the range of 0.01 to 0.5 μm.
Claim 5
Dependent Claim
40 words
A light emitting diode according to claim 1, wherein a peak wavelength of light obtained based on the light emissions effected by said first p-type layer and said second p-type layer is within the range of 460 to 470 nm.
Claim 6
Dependent Claim
20 words
A light emitting diode according to claim 1, wherein said acceptor impurities are aluminum and said donor impurities are nitrogen.
Claim 7
Dependent Claim
26 words
A light emitting diode according to claim 1, wherein said silicon carbide is of a polytype selected from the group consisting of 6H, 15R, and 4H.
Claim 8
Dependent Claim
144 words
A light emitting diode of silicon carbide having a p-n junction, comprising: an n-type layer of silicon carbide doped with donor impurities; a first p-type layer of silicon carbide formed on the n-type layer, said first p-type layer being doped with acceptor impurities and donor impurities; and a second p-type layer of silicon carbide formed on the first p-type layer, said second p-type layer being doped with acceptor impurities; wherein said first p-type layer has a thickness less than the diffusion length of electrons having flowed from said n-type layer under a forward bias condition, so that said first p-type layer effects light emission by donor-acceptor pairs caused by recombination with the electrons having flowed from said n-type layer, and said second p-type layer effects light emission related to the acceptor impurities caused by recombination with the electrons having flowed from said n-type layer.
Claim 9
Dependent Claim
144 words
A light emitting diode of silicon carbide having a p-n junction, comprising: an n-type layer of silicon carbide doped with donor impurities; a first p-type layer of silicon carbide formed on the n-type layer, said first p-type layer being doped with acceptor impurities and donor impurities; and a second p-type layer of silicon carbide formed on the first p-type layer, said second p-type layer being doped with acceptor impurities; wherein said first p-type layer has a thickness less than the diffusion length of electrons having flowed from said n-type layer under a forward bias condition, so that said first p-type layer effects light emission by donor-acceptor pairs caused by recombination with the electrons having flowed from said n-type layer, and said second p-type layer effects light emission related to the acceptor impurities caused by recombination with the electrons having flowed from said n-type layer.
Claim 10
Dependent Claim
39 words
A light emitting diode according to claim 7, wherein a third p-type layer is formed on said second p-type layer, said third p-type layer having a higher hole concentration than said first p-type layer and said second p-type layer.
Claim 11
Dependent Claim
25 words
A light emitting diode according to claim 7, wherein the thickness of said first p-type layer is within the range of 0.01 to 0.5 μm.
Claim 12
Dependent Claim
40 words
A light emitting diode according to claim 7, wherein a peak wavelength of light obtained based on the light emissions effected by said first p-type layer and said second p-type layer is within the range of 460 to 470 nm.
Claim 13
Dependent Claim
20 words
A light emitting diode according to claim 7, wherein said acceptor impurities are aluminum and said donor impurities are nitrogen.
Claim 14
Dependent Claim
26 words
A light emitting diode according to claim 7, wherein said silicon carbide is of a polytype selected from the group consisting of 6H, 15R, and 4H.
Claim 15
Dependent Claim
133 words
A light emitting diode, comprising: an n-type layer of silicon carbide doped with donor impurities; a first p-type layer of silicon carbide formed on the n-type layer; and a second p-type layer of silicon carbide formed on the first p-type layer, wherein one of said first and second p-type layers is doped with acceptor impurities, and the other of said first and second p-type layers is doped with acceptor impurities and donor impurities; wherein an application of a forward bias voltage across a p-n junction formed by said n-type layer and said first and second p-type layers produces emission of light which is substantially blue monochromatic; and wherein the first p-type layer has a thickness which is less than the diffusion length of electrons flowing from the n-type under s forward bias condition.
Claim 16
Dependent Claim
133 words
A light emitting diode, comprising: an n-type layer of silicon carbide doped with donor impurities; a first p-type layer of silicon carbide formed on the n-type layer; and a second p-type layer of silicon carbide formed on the first p-type layer, wherein one of said first and second p-type layers is doped with acceptor impurities, and the other of said first and second p-type layers is doped with acceptor impurities and donor impurities; wherein an application of a forward bias voltage across a p-n junction formed by said n-type layer and said first and second p-type layers produces emission of light which is substantially blue monochromatic; and wherein the first p-type layer has a thickness which is less than the diffusion length of electrons flowing from the n-type under s forward bias condition.
Claim 17
Dependent Claim
138 words
A light emitting diode according to, comprising: an n-type semiconductor layer doped with donor impurities; a first p-type semiconductor layer formed on the n-type semiconductor layer; and a second p-type semiconductor layer formed on the first p-type semiconductor layer, wherein one of said first and second p-type semiconductor layers is doped with acceptor impurities, and the other of said first and second p-type semiconductor layers is doped with acceptor impurities and donor impurities; wherein an application of a forward bias voltage across a p-n junction formed by said n-type semiconductor layer and said first and second p-type semiconductor layers produces emission of light which is substantially blue monochromatic; and wherein the first p-type semiconductor layer has a thickness which is less than the diffusion length of electrons flowing from the n-type semiconductor layer under a forward bias condition.
Claim 18
Dependent Claim
138 words
A light emitting diode according to, comprising: an n-type semiconductor layer doped with donor impurities; a first p-type semiconductor layer formed on the n-type semiconductor layer; and a second p-type semiconductor layer formed on the first p-type semiconductor layer, wherein one of said first and second p-type semiconductor layers is doped with acceptor impurities, and the other of said first and second p-type semiconductor layers is doped with acceptor impurities and donor impurities; wherein an application of a forward bias voltage across a p-n junction formed by said n-type semiconductor layer and said first and second p-type semiconductor layers produces emission of light which is substantially blue monochromatic; and wherein the first p-type semiconductor layer has a thickness which is less than the diffusion length of electrons flowing from the n-type semiconductor layer under a forward bias condition.
References Cited (Backward Citations)
US4918497A
Cited
US5027168A
Cited
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