Study on bonding of single bar high power semiconductor lasers.

Due to the mismatch between the thermal expansion coefficients of semiconductor laser chip and heat sink, giant thermal stresses will be generated after eutectic bonding. Immoderate thermal stress will cause the devices to produce the smile effect, making the coupling efficiency low. In this paper, we propose an approach to reduce thermal stress and improve the near-field linearity for semiconductor laser arrays. We optimize the eutectic bonding process by controlling the semiconductor laser chip and heat sink in different temperature fields through independent heat sources, to achieve the purpose of matching the shape variables earlier than welding. The heating temperature is determined by Suhir's deformation formula (Suhir E. Stresses in Bi-metal thermostats. J Appl Mech. 1986;53(3):657–660; Suhir E. Stresses in adhesively bonded Bi-material assemblies used in electronic packaging. MRS Proc. 1986;72). Then, finite element Analysis (FEA) was used for simulation verification. [ABSTRACT FROM AUTHOR]