Electronic Properties of GaN (0001) – Dielectric Interfaces

Transient Photoconductivity Studies of a-Si:H Interfaces

MRS Proceedings ◽

10.1557/proc-49-79 ◽

1985 ◽

Vol 49 ◽

Cited By ~ 2

Author(s):

R. A. Street

Keyword(s):

Electric Field ◽

Electronic Properties ◽

Metal Contacts ◽

Transient Photoconductivity ◽

Dielectric Interfaces

AbstractThe application of transient photoconductivity to the study of contacts and interfaces with a-Si:H is reviewed. The photocurrent is shown to contain three terms - one from the drift of photogenerated carriers, and two from contact and bulk effects due to the electric field induced by the drifting carriers. For different sample configurations, each of these terms can dominate, and each gives different information about a-Si:H bulk or surface electronic properties. The effects are illustrated with data from metal contacts, dielectric interfaces, doped layers and gap cell measurements.

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Electronic properties of semiconductor interfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126470 ◽

1987 ◽

Vol 45 ◽

pp. 334-337

Author(s):

Jerry Woodall

Keyword(s):

Fermi Level ◽

Electronic Properties ◽

Significant Role ◽

High Speed ◽

Laboratory Scale ◽

Metal Contacts ◽

Manufacturing Environment ◽

The Past ◽

Semiconductor Interfaces ◽

Dielectric Interfaces

Over the past decade III-V materials have been successfully commercialized for optoelectronic applications requiring LED's lasers and photodetectors. The success of these materials for these applications is based primarily on the use of heterojunction structures formed by epitaxial techniques in a manufacturing environment. More recently, III-V materials, notably GaAs, have been studied in the R&D environment as possible materials for use in high speed devices and circuits including VLSI. Even though the use of epitaxially grown structures has played a significant role in the success of laboratory scale devices and circuits, there are still several technology problems which will need to be solved before affordable manufacturing can be done. Two important challenges facing the commercialization of these materials for this application are metal contacts, and dielectrics for control and passivation. Both of these challenges are rooted in a common problem. Stated simply, the problem is that at nearly all GaAs/metal or dielectric interfaces the Fermi level is pinned near mid-gap.

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Structural properties of GaAs/InGaAs/GaAs (001) and InGaAs/GaAs (001) heterostructures and correlation with electronic properties

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176149 ◽

1990 ◽

Vol 48 (4) ◽

pp. 602-603

Author(s):

J.M. Bonar ◽

R. Hull ◽

R. Malik ◽

R. Ryan ◽

J.F. Walker

Keyword(s):

Band Gap ◽

Electronic Properties ◽

Gaas Substrate ◽

Critical Thickness ◽

Lattice Mismatch ◽

Band Offset ◽

Misfit Dislocations ◽

Gaas Substrates ◽

Gaas Structure ◽

Low X

In this study we have examined a series of strained heteropeitaxial GaAs/InGaAs/GaAs and InGaAs/GaAs structures, both on (001) GaAs substrates. These heterostructures are potentially very interesting from a device standpoint because of improved band gap properties (InAs has a much smaller band gap than GaAs so there is a large band offset at the InGaAs/GaAs interface), and because of the much higher mobility of InAs. However, there is a 7.2% lattice mismatch between InAs and GaAs, so an InxGa1-xAs layer in a GaAs structure with even relatively low x will have a large amount of strain, and misfit dislocations are expected to form above some critical thickness. We attempt here to correlate the effect of misfit dislocations on the electronic properties of this material.The samples we examined consisted of 200Å InxGa1-xAs layered in a hetero-junction bipolar transistor (HBT) structure (InxGa1-xAs on top of a (001) GaAs buffer, followed by more GaAs, then a layer of AlGaAs and a GaAs cap), and a series consisting of a 200Å layer of InxGa1-xAs on a (001) GaAs substrate.

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