Application of microwave scanning probes to photovoltaic materials

Author

Bertness, Kris A. ; Schlager, John B. ; Sanford, Norman A. ; Imtiaz, Atif ; Wallis, Thomas M. ; Weber, Joel C. ; Kabos, P. ; Mansfield, Lorelle M.

Author_Institution

NIST, Boulder, CO, USA

fYear

2010

fDate

20-25 June 2010

Abstract

We demonstrate that near-field scanning microwave microscopy (NSMM) can be used to detect photoresponse in photovoltaic materials with potential for submicrometer lateral resolution. In this approach, a radio-frequency scanning tunneling microscopy (RF-STM) tip is coupled to a resonant microwave cavity with a resonance near 4.5 GHz. The presence of additional mobile carriers in the vicinity of the probe tip changes the load on the cavity. These changes are quantified through the shifts in both the resonance frequency and quality factor Q. The changes in conductivity under illumination with blue light are easily detected for Cu(In,Ga)Se₂ and GaAs solar cell test material.

Keywords

cavity resonators; copper compounds; gallium arsenide; gallium compounds; indium compounds; near-field scanning optical microscopy; scanning tunnelling microscopy; solar cells; CIGS; GaAs; microwave scanning probes; near-field scanning microwave microscopy; photovoltaic materials; quality factor; radio-frequency scanning tunneling microscopy; resonance frequency; solar cell;

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.2010.5616057

Filename

5616057