超高圧電子顕微鏡によるGaP_1−xAs_x発光ダイオード中のミスフィット転位の解析

抄録

High-voltage electron microscopy investigation have been performed on (001) GaP/GaP_1−xAs_x grown by the chemical vapor deposition technique. In a continuous-graded specimen, dense and symmetric networks of ⟨110⟩ dislocations (10¹² m⁻² order) were observed in the graded layer but few dislocations propagated to the upper region, while in a step-graded specimen, inclined dislocations penetrated. The structural difference of dislocations is responsible for the difference in an emitting efficiency. Crystallographical and quantitative analysis of misfit dislocations such as Burger vector, slip plane, interaction and density was carried out in detail.