Photoluminescence studies of the electron-hole droplet and the impurity band in Si(P)

• Main Author: Rostworowski, Juan Adalberto
• Language: English
• Published: 2010
• Subjects: Photoluminescence; Exciton theory
• Online Access: http://hdl.handle.net/2429/20919

The photoluminescence spectrum of phosphorus-doped silicon at 17 _ 3 19-3 dopant concentrations ranging from 1.2 x 10¹⁷ cm⁻³ to 4.0 x 10¹⁹ cm⁻³ is studied as a function of excitation intensity. The spectra are interpreted tn terms of two types of recombination events', one' attributed to the recombination of oppositely charged carriers inside an electron-hole droplet and the other outside due to the recombination -of free holes with electrons in the impurity band. The latter type of event gives rise to a new photoluminescence peak observed for the first time. The line shape of this peak compares very well with a first principle calculation of the impurity band density of states within the Hubbard model. Existing theories for the ground state energy of an electron-hole droplet in n-type heavily doped silicon are reviewed and new numerical results are presented. However, within the present model droplets are not theoretically understood at this time in heavily-doped silicon. === Science, Faculty of === Physics and Astronomy, Department of === Graduate