beam irradiates the semiconductor surface to produce extremely high temperature in the irradiating region, so that the crystal damage can be repaired and the dislocation can be eliminated. It can effectively eliminate the lattice defects caused by ion implantation, and avoid damaging the shallow junction conductivity and other junction characteristics of integrated circuits due to the extremely short heating time (about one millionth of that of conventional thermal annealing).
The traditional heating annealing
technology is to put the whole workpiece in the vacuum furnace.
Laser annealing technology is mainly used to repair ion implanted semiconductor materials, especially silicon, at a certain temperature (300 ℃) °～ Annealing at 1200 ℃ for 10-60min.
Annealing is a kind of metal heat treatment process, which means that the metal is slowly heated to a certain temperature, maintained for enough time, and then cooled at an appropriate rate. The purpose is to reduce hardness and improve machinability; Eliminate residual stress, stabilize size, reduce deformation and crack tendency; Fine grain, adjust structure and eliminate structure defect. Accurately speaking, annealing is a kind of heat treatment process for materials, including metal materials and non-metal materials. Moreover, the annealing
purpose of new materials is different from that of traditional metals.
It is a clean and fast quenching process without water or oil. Compared with induction quenching, flame quenching and carburizing quenching, laser
quenching has the advantages of uniform hardening layer, high hardness (generally 1-3hrc higher than induction quenching), small deformation of workpiece, easy control of heating layer depth and heating track, easy automation, and no need to design corresponding induction coil according to different part size as induction quenching, The processing of large parts is not limited by the size of furnace during chemical heat treatment such as carburizing and quenching, so it is gradually replacing the traditional processes such as induction hardening and chemical heat treatment in many industrial fields. It is particularly important that the deformation of the workpiece before and after laser quenching can be ignored, so it is especially suitable for the surface heat treatment of parts with high precision requirements.