US5323027A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light emitting device with double heterostructure
Assignee: Shin-Etsu Handotai Co Ltd
•
Filing: 1992-05-29
•
Granted: 1994-06-21
•
Expires: 2012-05-29
Abstract
Abstract In a light emitting device comprising a first clad layer composed of a mixed crystal compound semiconductor of first type conductivity, an active layer composed of a mixed crystal compound semiconductor of first type conductivity which has the mixed crystal ratio required to emit the prescribed wavelength, and a second clad layer composed of a mixed crystal compound semiconductor of second type conductivity which has a mixed crystal ratio equivalent to that of the first clad layer, the active layer is sandwiched by the first and second clad layers and forms the double hetero structure with the first and second clad layers, and the carrier concentration in the first clad layer near the junction with the active layer was made to be 5×10 16 cm -3 or less. The carrier concentration in the active layer is preferably 1×10 17 cm -3 or less, and the carrier concentration in the second clad layer is preferably 5×10 16 cm -3 or more.
Inventors
- 👤 Masato Yamada
- 👤 Takao Takenaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:27
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10H20/822; H10H20/824; H10H20/8242; H10H20/811
Claims Analysis
Total Claims: 72
Claim 1
Independent Claim
129 words
A light emitting device, comprising: a first clad layer composed of a mixed crystal compound semiconductor of a first type conductivity; an active layer composed of a mixed crystal compound semiconductor of the first type conductivity which has a mixed crystal ratio required to emit the prescribed wavelength; and a second clad layer composed of a mixed crystal compound semiconductor of a second type conductivity which has a mixed crystal ratio equivalent to that of said first clad layer; wherein said active layer is sandwiched by said first and second clad layers and forms a double heterostructure with said first and second clad layers; and a carrier concentration in said first clad layer near the junction with said active layer is substantially less than 5×10 16 cm -3 .
Claim 2
Dependent Claim
129 words
A light emitting device, comprising: a first clad layer composed of a mixed crystal compound semiconductor of a first type conductivity; an active layer composed of a mixed crystal compound semiconductor of the first type conductivity which has a mixed crystal ratio required to emit the prescribed wavelength; and a second clad layer composed of a mixed crystal compound semiconductor of a second type conductivity which has a mixed crystal ratio equivalent to that of said first clad layer; wherein said active layer is sandwiched by said first and second clad layers and forms a double heterostructure with said first and second clad layers; and a carrier concentration in said first clad layer near the junction with said active layer is substantially less than 5×10 16 cm -3 .
Claim 3
Dependent Claim
24 words
A light emitting device in accordance with claim 1, wherein: a carrier concentration in said active layer is 1×10 17 cm -3 or less.
Claim 4
Dependent Claim
32 words
A light emitting device in accordance with claim 1, wherein: a carrier concentration in said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more.
Claim 5
Dependent Claim
47 words
A light emitting device in accordance with claim 1, wherein: a carrier concentration in said active layer is 1×10 17 cm -3 or less; and a carrier concentration in said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more.
Claim 6
Dependent Claim
32 words
A light emitting device in accordance with claim 1, wherein: an impurity added to said active layer and said first clad layer is an impurity selected from zinc (Zn) and carbon (C).
Claim 7
Dependent Claim
47 words
A light emitting device in accordance with claim 1, wherein: a carrier concentration of said active layer is 1×10 17 cm -3 or less; and an impurity added to said active layer and said first clad layer is an impurity selected from zinc (Zn) and carbon (C).
Claim 8
Dependent Claim
55 words
A light emitting device in accordance with claim 1, wherein: a carrier concentration in said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more; and an impurity added to said active layer and said first clad layer is an impurity selected from zinc (Zn) and carbon (C).
Claim 9
Dependent Claim
69 words
A light emitting device in accordance with claim 1, wherein: a carrier concentration of said active layer is 1×10 17 cm -3 or less; a carrier concentration is said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more; and an impurity added to said active layer and said first clad layer is an impurity selected from zinc (Zn) and carbon (C).
Claim 10
Dependent Claim
132 words
A light emitting device comprising: a first clad layer composed of a mixed crystal compound semiconductor represented as Ga 1-x Al x As (where 0<x<1) of first type conductivity; an active layer composed of a mixed crystal compound semiconductor represented as Ga 1-y Al y As (where 0<y<1) of first type of conductivity; and a second clad layer composed of a mixed crystal compound semiconductor of second type conductivity which has a mixed crystal ration equivalent to that of said clad layer; wherein said active layer is sandwiched by said first and second clad layers and forms a double heterostructure with said first and second clad layers; and the carrier concentration in said first clad layer near the junction with said active layer is substantially less than 5×10 16 cm -3 .
Claim 11
Dependent Claim
132 words
A light emitting device comprising: a first clad layer composed of a mixed crystal compound semiconductor represented as Ga 1-x Al x As (where 0<x<1) of first type conductivity; an active layer composed of a mixed crystal compound semiconductor represented as Ga 1-y Al y As (where 0<y<1) of first type of conductivity; and a second clad layer composed of a mixed crystal compound semiconductor of second type conductivity which has a mixed crystal ration equivalent to that of said clad layer; wherein said active layer is sandwiched by said first and second clad layers and forms a double heterostructure with said first and second clad layers; and the carrier concentration in said first clad layer near the junction with said active layer is substantially less than 5×10 16 cm -3 .
Claim 12
Dependent Claim
24 words
A light emitting device in accordance with claim 9, wherein: a carrier concentration of said active layer is 1×10 17 cm -3 or less.
Claim 13
Dependent Claim
32 words
A light emitting device in accordance with claim 9, wherein: a carrier concentration of said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more.
Claim 14
Dependent Claim
47 words
A light emitting device in accordance with claim 9, wherein: a carrier concentration of said active layer is 1×10 17 cm -3 or less; and a carrier concentration in said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more.
Claim 15
Dependent Claim
32 words
A light emitting device in accordance with claim 9, wherein: an impurity added to said active layer and said first clad layer is an impurity selected from zinc (Zn) and carbon (C).
Claim 16
Dependent Claim
47 words
A light emitting device in accordance with claim 9, wherein: a carrier concentration of said active layer is 1×10 17 cm -3 or less; and an impurity added to said active layer and said first clad layer is an impurity selected from zinc (Zn) and carbon (C).
Claim 17
Dependent Claim
55 words
A light emitting device in accordance with claim 9, wherein: a carrier concentration in said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more; and an impurity added to said active layer and said first clad layer is an impurity selected from zinc (Zn) and carbon (C).
Claim 18
Dependent Claim
69 words
A light emitting device in accordance with claim 9, wherein: a carrier concentration of said active layer is 1×10 17 cm -3 or less; a carrier concentration in said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more; and an impurity added to said active layer and said first clad layer is an impurity selected from zinc (Zn) and carbon (C).
Claim 19
Dependent Claim
24 words
A light emitting device, according to claim 9: wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 20
Dependent Claim
24 words
A light emitting device, according to claim 10: wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 21
Dependent Claim
24 words
A light emitting device, according to claim 11: wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 22
Dependent Claim
24 words
A light emitting device, according to claim 12: wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 23
Dependent Claim
24 words
A light emitting device, according to claim 13: wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 24
Dependent Claim
24 words
A light emitting device, according to claim 14: wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 25
Dependent Claim
24 words
A light emitting device, according to claim 15: wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 26
Dependent Claim
24 words
A light emitting device, according to claim 16: wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 27
Dependent Claim
19 words
A light emitting device, according to claim 9: wherein the impurity added to said second clad layer is Te.
Claim 28
Dependent Claim
19 words
A light emitting device, according to claim 10: wherein the impurity added to said second clad layer is Te.
Claim 29
Dependent Claim
19 words
A light emitting device, according to claim 11: wherein the impurity added to said second clad layer is Te.
Claim 30
Dependent Claim
19 words
A light emitting device, according to claim 12: wherein the impurity added to said second clad layer is Te.
Claim 31
Dependent Claim
19 words
A light emitting device, according to claim 13: wherein the impurity added to said second clad layer is Te.
Claim 32
Dependent Claim
19 words
A light emitting device, according to claim 14: wherein the impurity added to said second clad layer is Te.
Claim 33
Dependent Claim
19 words
A light emitting device, according to claim 15: wherein the impurity added to said second clad layer is Te.
Claim 34
Dependent Claim
19 words
A light emitting device, according to claim 16: wherein the impurity added to said second clad layer is Te.
Claim 35
Dependent Claim
143 words
A light emitting device having a carrier concentration in a first clad layer near a junction with an active layer which is substantially less than 5×10 16 cm -3 , made by a process comprising the steps of: sliding a first solution reservoir containing a p-type clad layer growth solution on a p-type gallium arsenide (GaAs) substrate; growing a p-type clad layer when the temperature is lowered from 900° C. to 800° C.; sliding a second solution reservoir containing a p-type active layer growth solution over said p-type gallium arsenide (GaAs) substrate; growing a p-type active layer while lowering the temperature from 800° C. to 795° C.; sliding a third solution reservoir containing an n-type clad layer growth solution over said p-type gallium arsenide (GaAs) substrate; and growing an n-type clad layer while the temperature is lowered from 795° C. to 650° C.
Claim 36
Dependent Claim
143 words
A light emitting device having a carrier concentration in a first clad layer near a junction with an active layer which is substantially less than 5×10 16 cm -3 , made by a process comprising the steps of: sliding a first solution reservoir containing a p-type clad layer growth solution on a p-type gallium arsenide (GaAs) substrate; growing a p-type clad layer when the temperature is lowered from 900° C. to 800° C.; sliding a second solution reservoir containing a p-type active layer growth solution over said p-type gallium arsenide (GaAs) substrate; growing a p-type active layer while lowering the temperature from 800° C. to 795° C.; sliding a third solution reservoir containing an n-type clad layer growth solution over said p-type gallium arsenide (GaAs) substrate; and growing an n-type clad layer while the temperature is lowered from 795° C. to 650° C.
Claim 37
Dependent Claim
28 words
A light emitting device in accordance with claim 33, wherein said process further comprises the step of sliding said third solution reservoir away from said n-type clad layer.
Claim 38
Dependent Claim
31 words
A light emitting device made by a process in accordance with claim 34, further comprising the step of selectively etching off of said p-type gallium arsenide (GaAs) substrate after epitaxial growth.
Claim 39
Dependent Claim
82 words
A light emitting device made by a process comprising the steps of: (a) forming a first clad semiconductor layer on a semiconductor substrate layer which is doped with an impurity; (b) diffusing said impurity from said first semiconductor substrate layer as an impurity source to said first clad semiconductor layer to have a predetermined carrier concentration profile, wherein a carrier concentration in said first clad layer near the junction with said active layer is substantially less than 5×10 16 cm -3 .
Claim 40
Dependent Claim
82 words
A light emitting device made by a process comprising the steps of: (a) forming a first clad semiconductor layer on a semiconductor substrate layer which is doped with an impurity; (b) diffusing said impurity from said first semiconductor substrate layer as an impurity source to said first clad semiconductor layer to have a predetermined carrier concentration profile, wherein a carrier concentration in said first clad layer near the junction with said active layer is substantially less than 5×10 16 cm -3 .
Claim 41
Dependent Claim
21 words
A light emitting device in accordance with claim 36, wherein said first semiconductor layer is an epitaxial layer grown by epitaxy.
Claim 42
Dependent Claim
32 words
A light emitting device in accordance with claim 36, wherein each of said first clad second semiconductor layer and semiconductor substrate layer consists of a semiconductor included by the III-V periodical group.
Claim 43
Dependent Claim
44 words
A light emitting device in accordance with claim 36, wherein said first clad semiconductor layer is an epitaxial layer grown by epitaxy; and each of said first clad semiconductor layer and said semiconductor substrate consist of a semiconductor included by the III-V periodical group.
Claim 44
Dependent Claim
25 words
A light emitting device in accordance with claim 36, wherein said semiconductor substrate consists of GaAs and said first clad semiconductor layer consists of GaAlAs.
Claim 45
Dependent Claim
18 words
A light emitting device in accordance with claim 36, wherein said semiconductor substrate layer is doped with Zn.
Claim 46
Dependent Claim
31 words
A light emitting device in accordance with claim 36, wherein said first clad semiconductor layer is an epitaxial layer grown by epitaxy; and said semiconductor substrate layer is doped with Zn.
Claim 47
Dependent Claim
40 words
A light emitting device in accordance with claim 36, wherein each of said semiconductor substrate layer and first clad semiconductor layer consists of a semiconductor included by the III-V periodical group; and said semiconductor substrate layer is doped with Zn.
Claim 48
Dependent Claim
35 words
A light emitting device in accordance with claim 36, wherein said semiconductor substrate layer consists of GaAs and said first clad semiconductor layer consists of GaAlAs; and said semiconductor substrate layer is doped with Zn.
Claim 49
Dependent Claim
51 words
A light emitting device in accordance with claim 36, wherein said first clad semiconductor layer is an epitaxial layer grown by epitaxy; each of said semiconductor substrate and first clad semiconductor layer consist of a semiconductor included by the III-V periodical group; and said semiconductor substrate layer is doped with Zn.
Claim 50
Dependent Claim
46 words
A light emitting device in accordance with claim 36, wherein said first clad semiconductor layer is an epitaxial layer grown by epitaxy; said semiconductor substrate layer consists of GaAs and said second semiconductor layer consists of GaAlAs; and said semiconductor substrate layer is doped with Zn.
Claim 51
Dependent Claim
29 words
A light emitting device in accordance with claim 36, wherein said semiconductor substrate layer has a carrier concentration equal to or higher than 5×10 17 atoms cm -3 .
Claim 52
Dependent Claim
38 words
A light emitting device in accordance with claim 36, wherein said semiconductor substrate layer is doped with Zn; and said semiconductor substrate layer has a carrier concentration equal to or higher than 5×10 17 atoms cm -3 .
Claim 53
Dependent Claim
41 words
A light emitting device in accordance with claim 36, wherein said step (b) of diffusing said impurity from said semiconductor substrate layer is carried out using heat generated in a step of forming said first clad semiconductor layer and/or other layers.
Claim 54
Dependent Claim
33 words
A light emitting device in accordance with claim 36, wherein a surface of said first clad semiconductor layer has a carrier concentration equal to or lower than 5×10 16 atoms cm -3 .
Claim 55
Dependent Claim
146 words
A light emitting device, comprising: a first clad layer composed of a mixed crystal compound semiconductor of a first type conductivity; an active layer composed of a mixed crystal compound semiconductor of the first type conductivity which has the mixed crystal ratio required to emit the prescribed wavelength; and a second clad layer composed of a mixed crystal compound semiconductor of a second type conductivity which has a mixed crystal ratio equivalent to that of said first clad layer; wherein said active layer is sandwiched by said first and second clad layers and forms a double heterostructure with said first and second clad layers; a carrier concentration in said first clad layer near the junction with said active layer is substantially less than 5×10 16 cm -3 ; and wherein an impurity added to said first clad layer is an impurity comprising zinc (Zn) and carbon.
Claim 56
Dependent Claim
146 words
A light emitting device, comprising: a first clad layer composed of a mixed crystal compound semiconductor of a first type conductivity; an active layer composed of a mixed crystal compound semiconductor of the first type conductivity which has the mixed crystal ratio required to emit the prescribed wavelength; and a second clad layer composed of a mixed crystal compound semiconductor of a second type conductivity which has a mixed crystal ratio equivalent to that of said first clad layer; wherein said active layer is sandwiched by said first and second clad layers and forms a double heterostructure with said first and second clad layers; a carrier concentration in said first clad layer near the junction with said active layer is substantially less than 5×10 16 cm -3 ; and wherein an impurity added to said first clad layer is an impurity comprising zinc (Zn) and carbon.
Claim 57
Dependent Claim
24 words
A light emitting device in accordance with claim 51, wherein a carrier concentration in said active layer is 1×10 17 cm -3 or less.
Claim 58
Dependent Claim
32 words
A light emitting device in accordance with claim 51, wherein a carrier concentration in said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more.
Claim 59
Dependent Claim
46 words
A light emitting device in accordance with claim 51, wherein carrier concentration in said active layer is 1×10 17 cm -3 or less; and a carrier concentration in said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more.
Claim 60
Dependent Claim
150 words
A light emitting device comprising: a first clad layer composed of a mixed crystal compound semiconductor represented as Ga 1-x Al x As (where 0<x<1) of a first type conductivity; an active layer composed of a mixed crystal compound semiconductor represented as Ga 1-y Al y As (where 0<y<1) of said first type of conductivity; a second clad layer composed of a mixed crystal compound semiconductor of a second type conductivity which has a mixed crystal ration equivalent to that of said clad layer; wherein said active layer is sandwiched by said first and second clad layers and forms a double heterostructure with said first and second clad layers; a carrier concentration in said first clad layer near the junction with said active layer is substantially less than 5×10 16 cm -3 ; and wherein an impurity added to said active layer is an impurity comprising zinc (Zn) and carbon.
Claim 61
Dependent Claim
150 words
A light emitting device comprising: a first clad layer composed of a mixed crystal compound semiconductor represented as Ga 1-x Al x As (where 0<x<1) of a first type conductivity; an active layer composed of a mixed crystal compound semiconductor represented as Ga 1-y Al y As (where 0<y<1) of said first type of conductivity; a second clad layer composed of a mixed crystal compound semiconductor of a second type conductivity which has a mixed crystal ration equivalent to that of said clad layer; wherein said active layer is sandwiched by said first and second clad layers and forms a double heterostructure with said first and second clad layers; a carrier concentration in said first clad layer near the junction with said active layer is substantially less than 5×10 16 cm -3 ; and wherein an impurity added to said active layer is an impurity comprising zinc (Zn) and carbon.
Claim 62
Dependent Claim
24 words
A light emitting device in accordance with claim 55, wherein a carrier concentration of said active layer is 1×10 17 cm -3 or less.
Claim 63
Dependent Claim
31 words
A light emitting device in accordance with claim 55, wherein a carrier concentration of said second layer near the junction with said active layer is 5×10 16 cm -3 or more.
Claim 64
Dependent Claim
47 words
A light emitting device in accordance with claim 55, wherein: a carrier concentration of said active layer is 1×10 17 cm -3 or less; and a carrier concentration in said second clad layer near the junction with said active layer is 5×10 16 cm -3 or more.
Claim 65
Dependent Claim
25 words
A light emitting device in accordance with claim 55, wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 66
Dependent Claim
25 words
A light emitting device in accordance with claim 56, wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 67
Dependent Claim
25 words
A light emitting device in accordance with claim 57, wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 68
Dependent Claim
25 words
A light emitting device in accordance with claim 58, wherein said x is between 0.6 and 0.85, and said y is between 0.3 and 0.45.
Claim 69
Dependent Claim
20 words
A light emitting device in accordance with claim 55, wherein an impurity added to said second clad layer is Te.
Claim 70
Dependent Claim
20 words
A light emitting device in accordance with claim 56, wherein an impurity added to said second clad layer is Te.
Claim 71
Dependent Claim
20 words
A light emitting device in accordance with claim 57, wherein an impurity added to said second clad layer is Te.
Claim 72
Dependent Claim
20 words
A light emitting device in accordance with claim 58, wherein an impurity added to said second clad layer is Te.
References Cited (Backward Citations)
EP0301893A2
Cited
EP0356037A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-06-20 | 1997-12-20 | 1998-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-06-20 | 2001-12-20 | 2002-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-06-20 | 2005-12-20 | 2006-06-21 | $7700.00 | Window Closed / Lapsed |