Hydrogen-mediated creation and annihilation of strain in amorphous silicon
- Xerox Palo Alto Research Center, 3333 Coyote Hill Road, Palo Alto, California 94304 (United States)
The influence of an increasing hydrogen concentration on the properties of hydrogenated amorphous silicon ({ital a}-Si:H) was investigated. An increase of the Si-H bond concentration by as much as 3{times}10{sup 21} cm{sup {minus}3} changes neither the defect density, the weak-bond density, nor the metastability. These results suggest that hydrogen is accommodated in pairs pinning the hydrogen chemical potential, which is indicative of a negative correlation energy. Data on annealing of {ital a}-Si:H at high temperatures show that the exponential band tails do not broaden as a function of the temperature. These experiments suggest that the random-network strain energy in device-quality {ital a}-Si:H is in metastable equilibrium. Based on our experimental results, we propose that internal strain propagates within the network and can be generated or reduced by annealing and/or the incorporation of hydrogen. According to maximum entropy the slope of the exponential band tails represents the average strain energy per lattice bond.
- OSTI ID:
- 165010
- Journal Information:
- Physical Review, B: Condensed Matter, Vol. 51, Issue 8; Other Information: PBD: 15 Feb 1995
- Country of Publication:
- United States
- Language:
- English
Similar Records
New microscopic model of the Staebler-Wronski effect in hydrogenated amorphous silicon
Research on the structural and electronic properties of defects in amorphous silicon