Electron beam induced current studies of strain balanced InGaAs/InGaAs multiquantum wells
| Autor: | Paul Abbott, Graham Clarke, Ravin Ginige, D. Diso, S. Tundo, L Lazzarini, Carsten Rohr, G. Torsello, Keith W. J. Barnham, L. Nasi, M. Mazzer |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Materials science
business.industry Mechanical Engineering Photoconductivity Electron beam-induced current Condensed Matter Physics law.invention Optics Absorption edge Mechanics of Materials law Thermophotovoltaic Solar cell Optoelectronics General Materials Science Metalorganic vapour phase epitaxy business Absorption (electromagnetic radiation) Dark current |
| Zdroj: | Materials science and technology 19 (2003): 977–980. doi:10.1179/026708303225004341 info:cnr-pdr/source/autori:Tundo S., Mazzer M., Lazzarini L., Nasi L., Torsello G., Diso D., Clarke G., Rohr C., Abbott P., Barnham K., Ginige R./titolo:Electron beam induced current studies of strain balanced InGaAs%2FInGaAs multiquantum wells/doi:10.1179%2F026708303225004341/rivista:Materials science and technology/anno:2003/pagina_da:977/pagina_a:980/intervallo_pagine:977–980/volume:19 |
| Popis: | Strain balanced InGaAs/InGaAs multiquantum well photovoltaic cells have been shown to be of great interest for thermophotovoltaic applications, where the absorption needs to extend well into the near infrared region to intercept most of the radiation emitted by heat sources operating in the range 1200-1700 degrees C. The present work has investigated In/sub y/Ga/sub 1-y/As/In/sub x/Ga/sub 1-x/As multiquantum well devices grown by metalorganic vapour phase epitaxy (MOVPE) on InP, and designed to have the absorption edge between 1800 and 2000 nm. Although strain balancing prevents misfit dislocations developing in the quantum wells, plastic relaxation may occur through the generation of conical defects when the difference between the compressive strain of the wells and the tensile strain of the barriers exceeds a critical value. Despite that they appear to be electrically active, these defects turn out to have a limited effect on the dark current of these cells, which is comparable to that of the best control cells (same structure but with no quantum wells). On the other hand, the conical defects appear to be correlated with the dramatic drop in the photocurrent even at a very low forward bias voltage. In the present study, electron beam induced current (EBIC) has been used to study the electrical properties of the defects on a microscopic scale, and made it possible to explain their influence on the electrical characteristics of the photovoltaic devices. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|