The study of the electronic structure of deep states associated with isolated, well characterised extended defects in semiconductors requires the use of a cathodoluminescence apparatus for TEM in the wavelength range 1-50 microns (1.2 - 0.02 eV). This would also allow the study of the III-V alloys and their defects used for I.R. emitters and lasers. Preliminary results using a grating spectrometer have been obtained by Petroff, however experience from Astronomy indicates that the Fellgett + Jacquinot advantage obtainable using Fourier Transform Infrared Spectroscopy (F.T.I.R.S.) is important for weak sources and noisy detectors. (See Davidson who has compared both techniques in SEM).The crucial design problem in the 1-10 micron range is the mirror movement in the Michelson Interferometer, which must be reproduceably positioned with submicron accuracy over a one centimeter range.
Extended Defects in Semiconductors
