Hole drift mobility measurements on a-Si: H using surface and uniformly absorbed illumination

Steluta A. Dinca, Eric Allan Schiff, Subhendu Guha, Baojie Yan, Jeff Yang

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

3 Scopus citations


The standard, time-of-flight method for measuring drift mobilities in semiconductors uses strongly absorbed illumination to create a sheet of photocarriers near an electrode interface. This method is problematic for solar cells deposited onto opaque substrates, and in particular cannot be used for hole photocarriers in hydrogenated amorphous silicon (a-Si:H) solar cells using stainless steel substrates. In this paper we report on the extension of the time-of-flight method that uses weakly absorbed illumination. We measured hole drift-mobilities on seven a-Si:H nip solar cells using strongly and weakly absorbed illumination incident through the n-layer. For thinner devices from two laboratories, the drift-mobilities agreed with each other to within a random error of about 15%. For thicker devices from United Solar, the drift-mobilities were about twice as large when measured using strongly absorbed illumination. We propose that this effect is due to a mobility profile in the intrinsic absorber layer in which the mobility decreases for increasing distance from the substrate.

Original languageEnglish (US)
Title of host publicationMaterials Research Society Symposium Proceedings
Number of pages6
StatePublished - 2009
Event2009 MRS Spring Meeting - San Francisco, CA, United States
Duration: Apr 14 2009Apr 16 2009


Other2009 MRS Spring Meeting
CountryUnited States
CitySan Francisco, CA


ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering
  • Mechanics of Materials

Cite this

Dinca, S. A., Schiff, E. A., Guha, S., Yan, B., & Yang, J. (2009). Hole drift mobility measurements on a-Si: H using surface and uniformly absorbed illumination. In Materials Research Society Symposium Proceedings (Vol. 1153, pp. 325-330)