Photoluminescence of heavily doped and compensated germanium

Abstract

The photoluminescence of heavily doped and compensated (hdc) germanium is investigated in a wide range of the compensation degree, K ≈ 0.05 to 0.99. The energetic position of the emission band, its halfwidth, kinetics, and integral intensity are measured as functions of excitation intensity, temperature, and compensation degree. For strong compensation the changes are very striking. The obtained results are discussed in terms of a tunnel recombination of charge carriers localized in potential minima of a random potential relief, arising from the random distribution of charged impurities. It is shown that the predictions of the model for strong compensation are in good quantitative agreement with the experimental observations.

Preparation and properties of heavily doped and strongly compensated Ge films on GaAs

“…7 There have been numerous works, both theoretical and experimental, to investigate the influence of electrostatic potential fluctuations, formed by correlated and uncorrelated distributions of impurities, on the electrical and optical properties of various single-crystalline semiconductors. [6][7][8][9][10][11][12][13][14][15][16] However, the problem is quite complex, and there still remain a number of major theoretical and experimental challenges. Besides, there are no sufficiently experimental works on heavily doped semiconductors with very high degree of compensation, in particular, fully compensated.…”

On the theory of absorption and luminescence spectra in amorphous semiconductors

“…Thus the relaxation and recombination may become strongly energy (and frequency) dependent. This is indeed observed in the kinetics of the luminescence process involving tail states [15,161. I n this case a broad distribution of decay times is found and particularly a faster decay of the high-energy portion of the luminescence intensity compared to its low-energy part is observed [15,161.…”

Radiative Recombination at Centres in Germanium–Silicon Solid Solutions

“…Thus, the change of EIC line energy with composition is totally (to within up to 0. of the Bohr radius (u) of the hydrogen-like state [2], and for small x is I n a semiconductor with non-direct bands in addition to the broadening of exciton lines there is an increase of the relative intensity of the zero-phonon line taking into account the contribution of recombination processes with momentum transfer to the isoelectronic atom. In particular, the addition of silicon atoms to germanium increases the intensity of the zero-phonon line of the free exciton [l], the same as the addition of germanium atoms to silicon [3].…”

“…Annihilation of free and bound excitons has been studied in [l] and the bands of donor-acceptor pair recombination have been investigated in [2]. At present there is only one work known 131 in the range of compositions rich in silicon.…”