Multi-stacked InAs/GaNAs quantum dots with direct Si doping for use in intermediate band solar cell

Author

Morioka, Takayuki ; Oshima, Ryuji ; Takata, Ayami ; Shoji, Yasushi ; Inoue, Takeru ; Kita, Takashi ; Okada, Yoshitaka

Author_Institution

Grad. Sch. of Eng., Univ. of Tokyo, Tokyo, Japan

fYear

2010

fDate

20-25 June 2010

Abstract

We investigated the effect of direct doping of quantum dots (QDs) with Si on the performance of QD solar cells (QDSCs). In order to control the Fermi level of intermediate band (IB) region, 25 layers of stacked InAs/GaNAs QDs were directly doped with Si impurity during the self-assembling stage of growth. A QDSC with Si doping shows an improved quantum efficiency (QE) in shorter wavelength region, which is from p-GaAs emitter layer. Further, the fact that applied external bias does not affect QE spectrum as well as photocurrent in QDSC with Si direct doping suggests that carrier collection has been enhanced in QD region as a result of reduction of recombination.

Keywords

III-V semiconductors; elemental semiconductors; gallium compounds; indium compounds; semiconductor doping; semiconductor quantum dots; silicon; solar cells; Fermi level; InAs-GaNAs; QD solar cells; QE spectrum; Si; applied external bias; carrier collection; direct Si doping; intermediate band region; intermediate band solar cell; multistacked quantum dots; photocurrent; quantum efficiency; self-assembling stage;

fLanguage

English

Publisher

ieee

Conference_Titel

Photovoltaic Specialists Conference (PVSC), 2010 35th IEEE

Conference_Location

Honolulu, HI

ISSN

0160-8371

Print_ISBN

978-1-4244-5890-5

Type

conf

DOI

10.1109/PVSC.2010.5615944

Filename

5615944