Hydrogen and Hydrogen-Related Defects in Silicon
Abstract
Results that contribute to an understanding of hydrogen and hydrogen-related defects in silicon are presented in this dissertation. The lattice locations of shallow donor impurity (As and Sb)-H complex in passivated silicon have been studied by means of ion channeling. The results show that the lattice locations of the donor impurities are dependent on the number of hydrogen which are involved in a donor-Si-H_{rm N} complex. In case of only one hydrogen associated with the donor in a complex, arsenic atoms are found to sit at the initial substitutional positions or with a displacement is less than 0.1 A. When more than one hydrogen involved in the donor-Si-H_{rm N} complex, donors (Sb) were displaced about 0.2 A along with <111> direction from the initial positions. The data are compared with recent predictions of the structure of the donor-Si-H_{rm N} complex in crystal silicon. The effects of reactive-ion etching and plasma etching (using deuterium) on the electrical properties of n-type and p-type silicon have been studied employing capacitance-voltage measurements of Schottky diodes and secondary ion mass spectrometry. Both methods show significant hydrogen penetration, which causes electrical deactivation of the n- or p-type dopants (boron, indium, and antimony), and radiation damage results from the plasma exposure. A phenomenon of hydrogen deactivation, including electrical, of p-type dopants in the deeper region during a very low temperature (~75 ^circC) post-annealing was found. A model for this is suggested to explain the results. After p-type (B-doped, 10^{15} cm^{-3}) and heavily doped n-type (Sb or As: 10^{19} to 10^{21} cm ^{-3}) silicon samples were exposed to D_2-plasmas, RBS and channeling spectra reveal that the near-surface damage is strongly dependent upon the electrical-conductivity-type of the silicon and the dopant concentration, but not on the total dose of hydrogen bombardment on the silicon surface. These experimental results can be explained by the model of a (donor) + (HcdotH) _ {rm N} molecule formation by a so -called "pick-off" reaction.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- 1992
- Bibcode:
- 1992PhDT........45Z
- Keywords:
-
- PASSIVATION;
- Physics: Condensed Matter; Engineering: Materials Science