The Effect of Charge Carrier Concentration and Structural Defects on the Raman Spectra of GaAs Single Crystals Grown by the Czochralski Method

Raman spectra of crystalline gallium arsenide grown by the Czochralski method have been studied. It has been demonstrated that the frequency of the coupled plasmon–phonon mode increases with increasing electron concentration n and approaches the frequency of the transverse vibration mode at n ~ 3 × 1018 cm−3. An increase in the hole concentration leads to a broadening of the longitudinal vibration peak. The relative intensity of the transverse mode decreases with an increase in the degree of disorder.