Detection of Interstitial Molecules in Wide Band Gap Materials Using Cathodoluminescence Microanalysis

Cathodoluminescence (CL) microanalysis (spectroscopy and microscopy) enables both pre-existing and irradiation induced defects in the bulk and surface defect structure of wide band gap materials (i.e. semiconductors and insulators) to be monitored and characterized with high spatial resolution and sensitivity. The local micro-volume of specimen may be selected for investigation by varying the electron beam parameters. CL micro analytical techniques allow the in situ monitoring of electron irradiation induced defects and the investigation of irradiation induced electromigration of mobile charged defect species. Irradiation can result in the formation of defects and /or the transformation of existing defect precursors. CL emissions from a material are usually associated with native and impurity defects of the host lattice, however in special cases CL microanalysis can provide direct or indirect evidence for the presence of interstitial molecular species in a material. Atomic displacements from the normal bonding (i.e. defect free) sites induced by an electron beam can result from either knock-on, or radiolytic processes, depending on the incident electron beam energy.

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Cathodoluminescence Microanalysis of Electron Irradiation Damage in Wide Band Gap Materials

MRS Proceedings ◽

10.1557/proc-540-43 ◽

1998 ◽

Vol 540 ◽

Cited By ~ 3

Author(s):

M.A. stevens Kalceff ◽

M.R. Phillips ◽

M. Toth ◽

A.R. Moon ◽

D.N. Jamieson ◽

...

Keyword(s):

Band Gap ◽

Electron Irradiation ◽

Depth Resolution ◽

Wide Band ◽

In Situ Monitoring ◽

Irradiation Damage ◽

Wide Band Gap ◽

Energetic Radiation ◽

Defect Species

AbstractCathodoluminescence (CL) microanalysis (spectroscopy and microscopy) in an electron microscope enables both pre-existing and irradiation induced local variations in the bulk and surface defect structure of wide band gap materials to be characterized with high spatial (lateral and depth) resolution and sensitivity. CL microanalytical techniques allow the in situ monitoring of electron irradiation induced damage, the post irradiation assessment of damage induced by other energetic radiation, and the investigation of irradiation induced electromigration of mobile charged defect species. Electron irradiated silicon dioxide polymorphs and MeV H+ ion implanted Type Ila diamond have been investigated using CL microanalytical techniques.

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Determination of deep level capture cross sections in wide band‐gap semiconductors by means of an electron beam

Journal of Applied Physics ◽

10.1063/1.328394 ◽

1980 ◽

Vol 51 (8) ◽

pp. 4523-4531 ◽

Cited By ~ 3

Author(s):

Oldwig von Roos

Keyword(s):

Electron Beam ◽

Band Gap ◽

Cross Sections ◽

Deep Level ◽

Wide Band ◽

Capture Cross ◽

Wide Band Gap ◽

Wide Band Gap Semiconductors ◽

Capture Cross Sections

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Interactions of wide band gap single crystals with 248 nm excimer laser radiation. III. The role of cleavage‐induced defects in MgO

Journal of Applied Physics ◽

10.1063/1.354489 ◽

1993 ◽

Vol 74 (6) ◽

pp. 3758-3767 ◽

Cited By ~ 44

Author(s):

J. T. Dickinson ◽

L. C. Jensen ◽

R. L. Webb ◽

M. L. Dawes ◽

S. C. Langford

Keyword(s):

Laser Radiation ◽

Band Gap ◽

Single Crystals ◽

Excimer Laser ◽

Wide Band ◽

Wide Band Gap ◽

Excimer Laser Radiation ◽

Induced Defects

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Vacancy-Type Defects in Electron and Proton Irradiated II-VI Compounds

MRS Proceedings ◽

10.1557/proc-510-437 ◽

1998 ◽

Vol 510 ◽

Cited By ~ 1

Author(s):

S. Brunner ◽

W. Puff ◽

P. Mascher ◽

A.G. Balogh

Keyword(s):

Band Gap ◽

Proton Irradiation ◽

Positron Lifetime ◽

Wide Band ◽

Compound Semiconductors ◽

Doppler Broadening ◽

Wide Band Gap ◽

Radiation Induced ◽

Induced Defects ◽

Mev Protons

AbstractIn this contribution we present a study aimed at comparing results of positron-lifetime and Doppler-broadening measurements on the wide-band-gap compound semiconductors ZnS, ZnSe, and ZnTe. To investigate the basic properties of intrinsic and radiation induced defects the samples were irradiated either with 3 MeV protons or 1 MeV electrons. The isochronal annealing was performed in an Ar atmosphere. It was found that electron and proton irradiation cause different changes in the positron annihilation characteristics. Several annealing stages were observed, related to the annealing of variously sized vacancy complexes.

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TEM and cathodoluminescence of precipitates in II-VI semiconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104509 ◽

1988 ◽

Vol 46 ◽

pp. 488-489

Author(s):

Joanna L. Batstone

Keyword(s):

Crystal Growth ◽

Band Gap ◽

Local Strain ◽

Wide Band ◽

Optoelectronic Device ◽

Wide Band Gap ◽

Bulk Crystal Growth ◽

Transmission Electron ◽

Device Applications ◽

Stoichiometry Control

Interest in II-VI semiconductors centres around optoelectronic device applications. The wide band gap II-VI semiconductors such as ZnS, ZnSe and ZnTe have been used in lasers and electroluminescent displays yielding room temperature blue luminescence. The narrow gap II-VI semiconductors such as CdTe and HgxCd1-x Te are currently used for infrared detectors, where the band gap can be varied continuously by changing the alloy composition x.Two major sources of precipitation can be identified in II-VI materials; (i) dopant introduction leading to local variations in concentration and subsequent precipitation and (ii) Te precipitation in ZnTe, CdTe and HgCdTe due to native point defects which arise from problems associated with stoichiometry control during crystal growth. Precipitation is observed in both bulk crystal growth and epitaxial growth and is frequently associated with segregation and precipitation at dislocations and grain boundaries. Precipitation has been observed using transmission electron microscopy (TEM) which is sensitive to local strain fields around inclusions.

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