1. Direct imaging of anisotropic minority-carrier diffusion in ordered GaInP.
- Author
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Haegel, N. M., Mills, T. J., Talmadge, M., Scandrett, C., Frenzen, C. L., Yoon, H., Fetzer, C. M., and King, R. R.
- Subjects
SCANNING electron microscopes ,HETEROSTRUCTURES ,ALLOYS ,SOLAR cells ,ANISOTROPY ,PHOSPHORS ,DIFFUSION - Abstract
An all-optical technique has been used to provide the first direct measurement of anisotropic minority-carrier diffusion in an ordered alloy of GaInP. Direct imaging of the minority-carrier diffusion distribution resulting from generation at a quasipoint source is obtained using an optical microscope coupled to a scanning electron microscope. Minority-carrier diffusion lengths ranging from 3 to 60 μm are measured by this technique in double heterostructures of GaInP, GaAs, and GaInAs, providing a key parameter of interest to the performance of state-of-the-art triple junction solar cells. Here we show a direct measurement of anisotropy in minority-carrier mobility in ordered GaInP, which is evident in the oval-shaped distribution of the recombination luminescence. A factor of 1.6 increase in minority electron mobility along the [110] major axis is reported. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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