US6087725A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low barrier ohmic contact for semiconductor light emitting device
Assignee: Panasonic Holdings Corp
•
Filing: 1998-09-28
•
Granted: 2000-07-11
•
Expires: 2018-09-28
Abstract
Abstract On a substrate of n-type GaAs, an n-type cladding layer of n-type Zn 0 .9 Mg 0 .1 S 0 .13 Se 0 .87, an n-type light guiding layer of n-type ZnS 0 .06 Se 0 .94, an active layer of ZnCdSe and a p-type light guiding layer of p-type ZnS 0 .06 Se 0 .94 are successively formed. On the p-type light guiding layer, a p-type contact structure is formed. The p-type contact structure includes a first layer of p-type ZnS 0 .31 Se 0 .54 Te 0 .15, a second layer of ZnS 0 .47 Se 0 .28 Te 0 .25, a third layer of p-type ZnS 0 .65 Te 0 .35, a fourth layer of p-type ZnS 0 .5 Te 0 .5 and a fifth layer of p-type ZnTe.
Inventors
- 👤 Shigeo Yoshii
- 👤 Yoichi Sasai
- 👤 Satoshi Kamiyama
- 👤 Tohru Saitoh
- 👤 Takashi Nishikawa
- 👤 Ryoko Miyanaga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:52
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/83; H10H20/832; H10H20/81; H10H20/822; H10H20/823
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
70 words
A semiconductor device comprising: a semiconductor layer of a p-type group II-VI compound semiconductor formed on a substrate; a first contact layer of ZnS w Se 1-w-x Te x , wherein 0<w<1, 0<x<1 and w+x<1, formed on said semiconductor layer; a second contact layer of ZnS 1-y Te y , wherein 0<y≦1, formed on said first contact layer; and an electrode of a metal formed on said second contact layer.
Claim 2
Dependent Claim
70 words
A semiconductor device comprising: a semiconductor layer of a p-type group II-VI compound semiconductor formed on a substrate; a first contact layer of ZnS w Se 1-w-x Te x , wherein 0<w<1, 0<x<1 and w+x<1, formed on said semiconductor layer; a second contact layer of ZnS 1-y Te y , wherein 0<y≦1, formed on said first contact layer; and an electrode of a metal formed on said second contact layer.
Claim 3
Dependent Claim
43 words
The semiconductor device of claim 1, wherein said substrate is made from GaAs or ZnSe, and said first contact layer has a composition matching in a lattice size with GaAs or ZnSe in at least a portion thereof closer to said semiconductor layer.
Claim 4
Dependent Claim
25 words
The semiconductor device of claim 2, wherein said first contact layer is made from ZnS w Se 1-w-x Te x , wherein 0.2<w≦0.65 and 0.05<x≦0.35.
Claim 5
Dependent Claim
58 words
The semiconductor device of claim 3, wherein said first contact layer includes a layer of ZnS w Se 1-w-x Te x , wherein 0.3<w≦0.4 and 0.1<x≦0.2, in a portion thereof closer to said semiconductor layer and a layer of ZnS w Se 1-w-x Te x , wherein 0.4<w≦0.5 and 0.2<x≦0.3, in another portion thereof closer to said electrode.
Claim 6
Dependent Claim
30 words
The semiconductor device of claim 1, wherein composition ratios of S and Te in said first contact layer are increased in a direction from said semiconductor layer toward said electrode.
Claim 7
Dependent Claim
17 words
The semiconductor device of claim 5, wherein said first contact layer includes plural layers having different compositions.
Claim 8
Dependent Claim
25 words
The semiconductor device of claim 5, wherein said first contact layer includes, in at least a portion thereof, a layer whose composition is continuously changed.
Claim 9
Dependent Claim
30 words
The semiconductor device of claim 1, wherein said substrate is made from GaAs or ZnSe, and said second contact layer is made from ZnS 1-y Te y , wherein 0.3<y≦1.
Claim 10
Dependent Claim
32 words
The semiconductor device of claim 8, wherein said second contact layer includes a layer of ZnS 1-y Te y , wherein 0.3<y<0.4, in a portion thereof closer to said first contact layer.
Claim 11
Dependent Claim
24 words
The semiconductor device of claim 1, wherein said second contact layer includes a layer of ZnTe in a portion thereof closer to said electrode.
Claim 12
Dependent Claim
31 words
The semiconductor device of claim 1, wherein a composition ratio of Te in said second contact layer is gradually increased in a direction from said first contact layer toward said electrode.
Claim 13
Dependent Claim
37 words
The semiconductor device of claim 1, wherein said semiconductor layer is made from ZnMgSSe, and said semiconductor device further includes a barrier relieving layer of ZnSe or ZnSSe between said semiconductor layer and said first contact layer.
Claim 14
Dependent Claim
112 words
A semiconductor light emitting device comprising: a first semiconductor layer of a group II-VI compound of a first conductivity type formed on a substrate; an active layer formed on said first semiconductor layer; a second semiconductor layer of a group II-VI compound of a second conductivity type formed on said active layer; and an electrode of a metal formed on said second semiconductor layer, wherein a first contact layer of ZnS w Se 1-w-x Te x , wherein 0<w≦1, 0<x<1 and w+x<1, and a second contact layer of ZnS 1-y Te y , wherein 0<y≦1, successively formed on said second semiconductor layer are sandwiched between said second semiconductor layer and said electrode.
Claim 15
Dependent Claim
112 words
A semiconductor light emitting device comprising: a first semiconductor layer of a group II-VI compound of a first conductivity type formed on a substrate; an active layer formed on said first semiconductor layer; a second semiconductor layer of a group II-VI compound of a second conductivity type formed on said active layer; and an electrode of a metal formed on said second semiconductor layer, wherein a first contact layer of ZnS w Se 1-w-x Te x , wherein 0<w≦1, 0<x<1 and w+x<1, and a second contact layer of ZnS 1-y Te y , wherein 0<y≦1, successively formed on said second semiconductor layer are sandwiched between said second semiconductor layer and said electrode.
Claim 16
Dependent Claim
36 words
The semiconductor light emitting device of claim 13, wherein said semiconductor light emitting device is a light emitting diode in which the first conductivity type is an n-type and the second conductivity type is a p-type.
Claim 17
Dependent Claim
38 words
The semiconductor light emitting device of claim 13, wherein said semiconductor light emitting device is a vertical cavity surface laser diode in which the first conductivity type is an n-type and the second conductivity type is a p-type.
References Cited (Backward Citations)
US4992837A
Cited
US5274269A
Cited
US5396103A
Cited
US5644165A
Cited
US5293074A
Cited
US5818072A
Cited
US5373175A
Cited
US5610413A
Cited
US5422902A
Cited
US5828086A
Cited
US5585649A
Cited
US5767536A
Cited
US5732099A
Cited
JPH0992930A
Cited
US5949093A
Cited
US5767534A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-07-11 | 2004-01-10 | 2004-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-07-11 | 2008-01-10 | 2008-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-07-11 | 2012-01-10 | 2012-07-11 | $7700.00 | Window Closed / Lapsed |