Diffusion, drift, and recombination of holes in a-Si: H

R. Schwarz, F. Wang, S. Grebner, Q. Gu, Eric Allan Schiff

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Scopus citations


We compare measurements in a-Si:H of ambipolar diffusion length Lamb (from steady-state photocarrier gratings (SSPG)) and hole drift χ(t) (from time-of-flight (TOF)). Using the response time tR from small-signal photocurrent decay measurements, we find that the equation Lamb 2 = 2(kT/e)χ(tR)/E is consistent with the measurements, where E is the electric field inducing hole drift in TOF. Several samples under different temperature and light intensity levels have been studied. This equation has several implications. Under the usual SSPG illumination conditions, electron-hole recombination occurs while holes are still occupying valence bandtail states; hence SSPG is not sensitive to hole capture by deep levels. Furthermore, the experiments show that the Einstein relation is valid for holes in a-Si:H. We are unaware of prior direct tests of this relation in an amorphous semiconductor.

Original languageEnglish (US)
Title of host publicationMaterials Research Society Symposium - Proceedings
EditorsMichael Hack, Eric A. Schiff, Arun Madan, Martin Powell, Akihisa Matsuda
PublisherMaterials Research Society
Number of pages10
StatePublished - 1995
Externally publishedYes
EventProceedings of the 1995 MRS Spring Meeting - San Francisco, CA, USA
Duration: Apr 18 1995Apr 21 1995


OtherProceedings of the 1995 MRS Spring Meeting
CitySan Francisco, CA, USA


ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials

Cite this

Schwarz, R., Wang, F., Grebner, S., Gu, Q., & Schiff, E. A. (1995). Diffusion, drift, and recombination of holes in a-Si: H. In M. Hack, E. A. Schiff, A. Madan, M. Powell, & A. Matsuda (Eds.), Materials Research Society Symposium - Proceedings (Vol. 377, pp. 427-436). Materials Research Society.