Schottky Diode with Asymmetric Metal Contacts on WS 2

One measure of the maturity of a device technology is the ease and reliability of applying contact metallurgy. Compared to metal contact of silicon, the status of GaAs metallization is still at its primitive stage. With the advent of GaAs MESFET and integrated circuits, very stringent requirements were placed on their metal contacts. During the past few years, extensive researches have been conducted in the area of Au-Ge-Ni in order to lower contact resistances and improve uniformity. In this paper, we report the results of TEM study of interfacial reactions between Ni and GaAs as part of the attempt to understand the role of nickel in Au-Ge-Ni contact of GaAs.N-type, Si-doped, (001) oriented GaAs wafers, 15 mil in thickness, were grown by gradient-freeze method. Nickel thin films, 300Å in thickness, were e-gun deposited on GaAs wafers. The samples were then annealed in dry N2 in a 3-zone diffusion furnace at temperatures 200°C - 600°C for 5-180 minutes. Thin foils for TEM examinations were prepared by chemical polishing from the GaA.s side. TEM investigations were performed with JE0L- 100B and JE0L-200CX electron microscopes.

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The morphologies and electrical properties of indium contacts on (100) cadmium telluride surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131747 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1422-1423

Author(s):

A.M. Letsoalo ◽

M.E. Lee ◽

E.O. de Neijs

Keyword(s):

Electrical Properties ◽

Cadmium Telluride ◽

Methanol Solution ◽

Electrical Characteristics ◽

Metal Contacts ◽

Deposition Technique ◽

Interfacial Layers ◽

Semiconductor Contacts ◽

Grown Single Crystal ◽

Diamond Abrasive

Semiconductor devices require metal contacts for efficient collection of electrical charge. The physics of these metal/semiconductor contacts assumes perfect, abrupt and continuous interfaces between the layers. However, in practice these layers are neither continuous nor abrupt due to poor nucleation conditions and the formation of interfacial layers. The effects of layer thickness, deposition rate and substrate stoichiometry have been previously reported. In this work we will compare the effects of a single deposition technique and multiple depositions on the morphology of indium layers grown on (100) CdTe substrates. The electrical characteristics and specific resistivities of the indium contacts were measured, and their relationships with indium layer morphologies were established.Semi-insulating (100) CdTe samples were cut from Bridgman grown single crystal ingots. The surface of the as-cut slices were mechanically polished using 5μm, 3μm, 1μm and 0,25μm diamond abrasive respectively. This was followed by two minutes immersion in a 5% bromine-methanol solution.

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Temperature-Dependent Logic Failure in a GaAs Power Amplifier-Duplexer Module Caused by a Subtle Parasitic Schottky Diode

ISTFA 2014: Conference Proceedings from the 40th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2014p0450 ◽

2014 ◽

Author(s):

Rose Emergo ◽

Steve Brockett ◽

Pat Hamilton

Keyword(s):

Power Amplifier ◽

Schottky Diode ◽

Production Test ◽

Temperature Dependent ◽

Cold Temperatures ◽

Collector Junction ◽

Power Mode ◽

The Difference ◽

Base Contact ◽

Single Power

Abstract A single power amplifier-duplexer device was submitted by a customer for analysis. The device was initially considered passing when tested against the production test. However, further electrical testing suggested that the device was stuck in a single power mode for a particular frequency band at cold temperatures only. This paper outlines the systematic isolation of a parasitic Schottky diode formed by a base contactcollector punch through process defect that pulled down the input of a NOR gate leading to the incorrect logic state. Note that this parasitic Schottky diode is parallel to the basecollector junction. It was observed that the logic failure only manifested at colder temperatures because the base contact only slightly diffused into the collector layer. Since the difference in the turn-on voltages between the base-collector junction and the parasitic Schottky diode increases with decreasing temperature, the effect of the parasitic diode is only noticeable at lower temperatures.

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Methodology for Analysis of Schottky Diode Failures

ISTFA 2010: Conference Proceedings from the 36th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2010p0449 ◽

2010 ◽

Author(s):

Bhanu P. Sood ◽

Michael Pecht ◽

John Miker ◽

Tom Wanek

Keyword(s):

Failure Mode ◽

Schottky Diode ◽

Failure Modes ◽

Schottky Diodes ◽

Failure Mechanisms ◽

Forward Voltage ◽

Fast Switching ◽

Voltage Drops ◽

The Common

Abstract Schottky diodes are semiconductor switching devices with low forward voltage drops and very fast switching speeds. This paper provides an overview of the common failure modes in Schottky diodes and corresponding failure mechanisms associated with each failure mode. Results of material level evaluation on diodes and packages as well as manufacturing and assembly processes are analyzed to identify a set of possible failure sites with associated failure modes, mechanisms, and causes. A case study is then presented to illustrate the application of a systematic FMMEA methodology to the analysis of a specific failure in a Schottky diode package.

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Pseudomorphic GaInP Schottky diode and MSM detector on InP

Electronics Letters ◽

10.1049/el:19900316 ◽

1990 ◽

Vol 26 (7) ◽

pp. 487 ◽

Cited By ~ 6

Author(s):

S. Loualiche ◽

A. le Corre ◽

A. Ginudi ◽

L. Henry ◽

C. Vaudry ◽

...

Keyword(s):

Schottky Diode

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