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EP0312237A2
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Interface charge enhancement in delta-doped heterostructure
Assignee: AT&T Inc
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Filing: 1988-10-05
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Granted: —
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Expires: 2008-10-05
Abstract
Abstract Interface carrier density for a selectively doped heterostructure (31, 32, 34) in a semiconductor device such as a field effect transistor is increased by forming a delta-doped channel layer (33) in close proximity to a heterointerface (40) and conduction channel (39). In this structure, two quantum mechanical systems (a planar sheet of charge carriers and the heterointerface) cooperate to reduce a selected barrier thickness below the thickness of an undoped semiconductor spacer layer (32) separating the two systems. The delta-doped layer (33) can be grown between the spacer layer (32) and the doped semiconductor donor layer (34), but it can as well be grown within the spacer layer (32) or within a semiconductor quantum well layer (63) grown over the spacer layer (32).
Inventors
- 👤 John Edward Cunningham
- 👤 Erdmann Fred Schubert
- 👤 Won-Tien Tsang
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 16:54
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/40; H10D30/47; H10D30/471; H10D30/475; H10D30/4755; H10D62/00; H10D62/60; H10D62/605
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
97 words
A semiconductor structure comprising a first semiconductor layer comprised of a first material composition a second semiconductor layer comprised of a second material composition, said first and second semiconductor layers substantially abutting along a common boundary to form a heterointerface therealong, said structure being characterized in that said second semiconductor layer includes an atomic planar layer comprised of a third material composition for delta doping said second semiconductor layer at a predetermined distance from said heterointerface, a doping density of said atomic planar layer being sufficiently high to reduce a selected barrier thickness below said predetermined distance.
Claim 2
Dependent Claim
97 words
A semiconductor structure comprising a first semiconductor layer comprised of a first material composition a second semiconductor layer comprised of a second material composition, said first and second semiconductor layers substantially abutting along a common boundary to form a heterointerface therealong, said structure being characterized in that said second semiconductor layer includes an atomic planar layer comprised of a third material composition for delta doping said second semiconductor layer at a predetermined distance from said heterointerface, a doping density of said atomic planar layer being sufficiently high to reduce a selected barrier thickness below said predetermined distance.
Claim 3
Dependent Claim
25 words
The semiconductor structure defined in Claim 1 wherein the first and second material compositions are selected from the group consisting of Group III-V semiconductor compounds.
Claim 4
Dependent Claim
49 words
The semiconductor structure defined in Claim 1 wherein the first material composition is comprised of gallium arsenide, the second material composition is comprised of aluminium gallium arsenide, and the third material composition is chosen from the group consisting of n-type and p-type dopant materials for a gallium arsenide system.
Claim 5
Dependent Claim
34 words
The semiconductor structure defined in Claim 1 or 2 or 3 wherein said predetermined distance is greater than 0 Angstroms and said doping density is greater than or equal to 4.0 x 10¹² cm⁻².
Claim 6
Dependent Claim
14 words
The semiconductor structure defined in Claim 4 wherein said third material composition includes silicon.
Claim 7
Dependent Claim
119 words
A semiconductor structure comprising a first semiconductor layer comprised of a first material composition a second semiconductor layer comprised of a second material composition, said first and second semiconductor layers substantially abutting along a common boundary to form a heterointerface therealong, said structure being characterized in that said second semiconductor includes at least one quantum well region comprised of a third material composition, said at lest one quantum well region including an atomic planar layer comprised of a fourth material composition for delta doping, said at least one quantum well region at a predetermined distance from said heterointerface, a doping density of said atomic planar layer being sufficiently high to reduce a selected barrier thickness below said predetermined distance.
Claim 8
Dependent Claim
119 words
A semiconductor structure comprising a first semiconductor layer comprised of a first material composition a second semiconductor layer comprised of a second material composition, said first and second semiconductor layers substantially abutting along a common boundary to form a heterointerface therealong, said structure being characterized in that said second semiconductor includes at least one quantum well region comprised of a third material composition, said at lest one quantum well region including an atomic planar layer comprised of a fourth material composition for delta doping, said at least one quantum well region at a predetermined distance from said heterointerface, a doping density of said atomic planar layer being sufficiently high to reduce a selected barrier thickness below said predetermined distance.
Claim 9
Dependent Claim
26 words
The semiconductor structure defined in Claim 6 wherein the first, second and third material compositions are selected from the group consisting of Group III-V semiconductor compounds.
Claim 10
Dependent Claim
51 words
The semiconductor structure defined in Claim 6 wherein the first and third material compositions are comprised of gallium arsenide, the second material composition is comprised of aluminum gallium arsenide, and the fourth material composition is chosen from the group consisting of n-type and p-type dopant materials for a gallium arsenide system.
Claim 11
Dependent Claim
34 words
The semiconductor structure defined in Claim 6 or 7 or 8 wherein said predetermined distance is greater than 0 Angstroms and said doping density is greater than or equal to 4.0 x 10¹² cm⁻².
Claim 12
Dependent Claim
30 words
The semiconductor structure defined in Claim 9 wherein said at least one quantum well region is less than or equal to 10 Angstroms thick as measured normal to said heterointerface.
Claim 13
Dependent Claim
15 words
The semiconductor structure as defined in Claim 9 wherein said fourth material composition includes silicon.
Claim 14
Dependent Claim
15 words
The semiconductor structure as defined in Claim 10 wherein said fourth material composition includes silicon.
References Cited (Backward Citations)
No citation records indexed.
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