Evaluation of p-Type Doping for (1,1,-2,0) Epitaxial Layers Grown on α-Cut (1,1,-2,0) 4H-SiC Substrates

A sublimation epitaxial method, referred to as the Closed Space Technique (CST) was adopted to produce thick SiC epitaxial layers for power device applications. In this study, we aimed to systematically investigate surface morphologies and electrical properties of SiC epitaxial layers grown with varying a SiC/Al ratio in a SiC source powder during the sublimation growth using the CST method. It was confirmed that the acceptor concentration of epitaxial layer was continuously decreased with increasing the SiC/Al ratio. The blue light emission was successfully observed on a PN diode structure fabricated with the p-type SiC epitaxial layer. Furthermore, 4H-SiC MESFETs having a micron-gate length were fabricated using a lithography process and their current-voltage performances were characterized.

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Selective Area Deposition of Passivants, Insulators, and Epitaxial Films of II-VI Compound Semiconductors

MRS Proceedings ◽

10.1557/proc-161-159 ◽

1989 ◽

Vol 161 ◽

Author(s):

D.L. Dreifus ◽

Y. Lansari ◽

J.W. Han ◽

S. Hwang ◽

J.W. Cook ◽

...

Keyword(s):

Ohmic Contacts ◽

Epitaxial Films ◽

Semiconductor Surface ◽

Epitaxial Layers ◽

Double Crystal ◽

Surface Areas ◽

Selective Area ◽

Lift Off ◽

P Type ◽

Area Deposition

ABSTRACTII-VI semiconductor surface passivants, insulators, and epitaxial films have been deposited onto selective surface areas by employing a new masking and lift-off technique. The II-VI layers were grown by either conventional or photoassisted molecular beam epitaxy (MBE). CdTe has been selectively deposited onto HgCdTe epitaxial layers as a surface passivant. Selective-area deposition of ZnS has been used in metal-insulator-semiconductor (MIS) structures. Low resistance ohmic contacts to p-type CdTe:As have also been realized through the use of selectively-placed thin films of the semi-metal HgTe followed by a thermal evaporation of In. Epitaxial layers of HgTe, HgCdTe, and HgTe-CdTe superlattices have also been grown in selective areas on CdZnTe substrates, exhibiting specular morphologies and double-crystal x-ray diffraction rocking curves (DCXD) with full widths at half maximum (FWHMs) as narrow as 140 arcseconds.

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High hole concentration of p-type InGaN epitaxial layers grown by MOCVD

Thin Solid Films ◽

10.1016/j.tsf.2005.07.084 ◽

2006 ◽

Vol 498 (1-2) ◽

pp. 113-117 ◽

Cited By ~ 15

Author(s):

Po-Chang Chen ◽

Chin-Hsiang Chen ◽

Shoou-Jinn Chang ◽

Yan-Kuin Su ◽

Ping-Chuan Chang ◽

...

Keyword(s):

Hole Concentration ◽

Epitaxial Layers ◽

High Hole Concentration ◽

P Type

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Measuring Diffusion Lengths in Epitaxial Silicon by Surface Photovoltage

MRS Proceedings ◽

10.1557/proc-386-207 ◽

1995 ◽

Vol 386 ◽

Author(s):

John Lowell ◽

Valerie Wenner ◽

Damon Debusk

Keyword(s):

Transition Metals ◽

Optical Filters ◽

Surface Photovoltage ◽

Epitaxial Layers ◽

Device Performance ◽

Optical Surface ◽

Epitaxial Silicon ◽

Type Silicon ◽

P Type ◽

And Diffusion

ABSTRACTIn CMOS, the use of epitaxial layers for prevention of latch-up in logic technologies is well-known and pervasive. One of the crucial parameters is the amount of metallic contamination due to transition metals such as Fe in the epi since this phenomena effects both device performance and quality. However, the ability to measure this parameter on product material is not generally available due to inherent problems with most known methods. The limitation of traditional surface photovoltage is that the deep optical penetration of over a hundred microns is well-beyond the depth of most epitaxial layers and does not accurately profile the epitaxial region [1]. In this paper we report on the application of optical surface photovoltage (SPV) using a set of ultra-shallow optical filters to both quantify and qualify as-grown epitaxial layers on CZ P-type silicon. We believe that a non-contact, SPV measurement of Fe concentration and diffusion lengths within an epitaxial region has not been previously reported.

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Properties of 4H-SiC by Sublimation Close Space Technique

MRS Proceedings ◽

10.1557/proc-572-179 ◽

1999 ◽

Vol 572 ◽

Author(s):

S. Nishino ◽

K. Matsumoto ◽

Y. Chen ◽

Y. Nishio

Keyword(s):

Schottky Diode ◽

Source Material ◽

Epitaxial Layers ◽

Power Devices ◽

High Quality ◽

Substrate Quality ◽

Space Technique ◽

P Type ◽

Type Conduction

ABSTRACTSiC is suitable for power devices but high quality SiC epitaxial layers having a high breakdown voltage are needed and thick epilayer is indispensable. In this study, CST method (Close Space Technique) was used to rapidly grow thick epitaxial layers. Source material used was 3C-SiC polycrystalline plate of high purity while 4H-SiC(0001) crystals inclined 8° off toward <1120> was used for the substrate. Quality of the epilayer was influenced significantly by pressure during growth and polarity of the substrate. A p-type conduction was obtained by changing the size of p-type source material. The carrier concentration of epilayer decreased when a lower pressure was employed. Schottky diode was also fabricated.

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Electrical characteristics and structural properties of ohmic contacts to p-type 4H-SiC epitaxial layers

Semiconductors ◽

10.1134/1.1187850 ◽

1999 ◽

Vol 33 (11) ◽

pp. 1206-1211 ◽

Cited By ~ 12

Author(s):

K. V. Vasilevskii ◽

S. V. Rendakova ◽

I. P. Nikitina ◽

A. I. Babanin ◽

A. N. Andreev ◽

...

Keyword(s):

Structural Properties ◽

Ohmic Contacts ◽

Epitaxial Layers ◽

Electrical Characteristics ◽

P Type

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Above bandgap luminescence of p-type GaAs epitaxial layers

Solid State Communications ◽

10.1016/0038-1098(91)90048-z ◽

1991 ◽

Vol 79 (6) ◽

pp. 543-546 ◽

Cited By ~ 7

Author(s):

J. Sapriel ◽

J. Chavignon ◽

F. Alexandre ◽

R. Azoulay ◽

B. Sermage ◽

...

Keyword(s):

Epitaxial Layers ◽

P Type

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GaAs epitaxial layers obtained by close-spaced vapor transport in H2 + H2O and H2 + CO2 ambients: Fine control of the growth rate and its effect on the electrical properties of the layers

Canadian Journal of Physics ◽

10.1139/p94-008 ◽

1994 ◽

Vol 72 (1-2) ◽

pp. 44-50

Author(s):

D. Cossement ◽

Z. Huang ◽

G. Perron ◽

B. Jean ◽

J. P. Dodelet

Keyword(s):

Growth Rate ◽

Water Vapor ◽

Vapor Pressure ◽

Water Vapor Pressure ◽

Vapor Transport ◽

Epitaxial Layers ◽

Fine Control ◽

Experimental Values ◽

P Type

In view of developing the close-spaced vapor transport technique (CSVT) to obtain III/V homojunction solar cells, it is necessary to finely control the growth rate of GaAs epitaxial layers. This has been performed either by controlling the water vapor pressure, [Formula: see text] injected in the reactor along with H2, in H2 + H2O ambient, or by controlling the water vapor pressure generated in situ by the reaction of H2 + CO2 in the reactor. For H2 + CO2 ambient, [Formula: see text], controls [Formula: see text] according to the following reaction: [Formula: see text]. The growth rates calculated with a diffusion controlled model are in agreement with the experimental values for both ambients, including the observation of a maximum in the evolution of the growth rate with [Formula: see text], Controlling the growth rate of GaAs by changing [Formula: see text] affects the carrier density (NA–ND) of p-type layers grown from Zn-doped GaAs sources. In both ambients (NA–ND) is a function of [Formula: see text]. Such a behavior is also obtained for the calculated carrier densities. It is the result of the transport of Zn as ZnO in CSVT. In H2 + CO2 ambient, where H2O and C are generated in situ, carbon is not incorporated as a major p-type doping impurity, contrarily to expectations, n-type GaAs layers were also obtained from Te-doped GaAs sources. In that case, the measured NA–ND values are not affected by changes in [Formula: see text] because water is not involved in the transport of Te in CSVT.

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Study of Ohmic Contacts on P-Type ZnSe and ZnSe Epitaxial Layers Grown by Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-281-727 ◽

1992 ◽

Vol 281 ◽

Author(s):

C. Piskoti ◽

B. Mykolajenko ◽

M. Vaziri

Keyword(s):

Molecular Beam Epitaxy ◽

Ohmic Contact ◽

Ohmic Contacts ◽

Molecular Beam ◽

Metal Contact ◽

Epitaxial Layers ◽

Preliminary Results ◽

Current Voltage ◽

Current Voltage Characteristics ◽

P Type

ABSTRACTTo study the formation of ohmic contacts, several metals have been deposited on p-types ZnTe and ZnSe epitaxial layers. The metals were deposited on the layers either by simple evaporation or by electroplating. The current-voltage characteristics associated with each metal contact were measured. The preliminary results of these measurements indicate that electroplating is a better technique for making ohmic contact to these layers.

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