Experimental investigation of influence of scratch features on GaAs cleavage plane during cleavage processing using a scratching capability index

Abstract

High-power semiconductor laser cavities are formed via the cleavage plane, and critically influence the reliability and performance of the laser. This paper investigates both the scratching operation and the cleavage operation to improve the quality of the cleavage plane during the entire cleavage process. The scratching capability index (SCI) variable was proposed to evaluate the scratch quality of GaAs. A series of scratching and cleavage experiments were carried out to investigate the effect of the scratch features on the GaAs cleavage plane. Experimental results of the scratching operation showed that a smaller scratching load and higher scratching speed were beneficial for reducing the kerf width and damage area width of GaAs. The cleavage operation on GaAs {100} cleavage planes exhibited crack propagation in the [101] and [100] directions and a slip direction in the crystal direction. The calculated SCI variable correlated well with the scratch and cleavage qualities of GaAs, where a higher scratching SCI correlated with a smoother GaAs cleavage plane during cleavage processing. Thus, the SCI has the potential to relate the scratching parameters with the resulting cleavage plane quality of GaAs, which will help improve the manufacturing of semiconductor laser chips in the future.