The Theory of Thermal Dechanneling from Axial Channels

In the past few years, there has been rapid growth in the positron annihilation spectroscopy (PAS) of overlayers, interfaces, and buried regions of semiconductors. There are few other techniques that are as sensitive as PAS to low concentrations of open-volume-type defects. The characteristics of the annihilation gamma rays depend strongly on the local environment of the annihilation sites and are used to probe defect concentrations in a range inaccessible to conventional defect probes, yet which are important in the electrical performance of device structures. We show how PAS can be used as a nondestructive probe to examine defects in technologically important Si-based structures. The discussion will focus on the quality of overlayers, formation and annealing of defects after ion implantation, identification of defect complexes, and evaluation of the distribution of internal electric fields. We describe investigations of the activation energy for the detrapping of hydrogen from SiO2−Si interface trap centers, variations of interface trap density, hole trapping at SiO2−Si interfaces, and radiation damage in SiO2−Si systems. We also briefly summarize the use of PAS in compound semiconductor systems and suggest some future directions.

show abstract

Effect of annealing on the defect structure in a-SiC:H films

Friessnegg

Boudreau

Brown

et al. 1996

Journal of Applied Physics

View full text Add to dashboard Cite

The annealing behavior of amorphous, hydrogenated silicon carbide films in the range 400-900°C was studied by optical characterization methods, 15 N hydrogen profiling, and defect profiling using a variable energy positron beam. The films were deposited in an electron cyclotron resonance chemical vapor deposition system using ditertiary butyl silane ͓SiH 2 ͑C 4 H 9 ͒ 2 ͔ as the monosource for silicon and carbon. As-deposited films were found to contain large concentrations of hydrogen, both bonded and unbonded. Under rapid thermal annealing in a N 2 atmosphere, the bonded hydrogen effuses giving rise to additional Si-C bond formation and to film densification. After annealing at high temperatures in N 2 , a marked decrease in the total hydrogen content is observed. After annealing in vacuum, however, the hydrogen effusion promotes void formation in the films.

show abstract

The Theory of Thermal Dechanneling from Axial Channels

Cited by 5 publications

References 4 publications

Axial blocking in a master equation approach

Axial blocking in a master equation approach

Characterization of defects in Si and SiO2−Si using positrons

Effect of annealing on the defect structure in a-SiC:H films

Contact Info

Product

Resources

About