The ice tray chemical mechanical polishing monocrystalline gallium arsenide chip Mechanism and Technology Research
|Course||Materials Processing Engineering|
|Keywords||Single crystal gallium arsenide chip Brittle ductile transition The nano silica abrasive ice tray The ice tray chemical mechanical polishing Surface roughness|
Single crystal gallium arsenide materials is the development of a new generation following the germanium, single crystal silicon semiconductor material. It is one of the most important, the most mature of compound semiconductor materials, mainly used in the fields of optoelectronics and microelectronics. Gallium arsenide is typical of hard and brittle materials, its plasticity is low, the the ordinary processing technology and the corresponding process parameters and processing, will only lead to its brittle crack removal will not exist in the processing of surface like metal obvious shear flow phenomenon, and when the cutting force is too large, the material will be brittle fracture occurs, and this will affect the quality and integrity of the surface being processed. Characteristics of single crystal gallium arsenide chip ultra-precision machining, around the frozen ice made of nano-silica abrasive disk as a single crystal gallium arsenide chip polishing pad for chemical mechanical polishing of single crystal gallium arsenide chip to carry out research work explores the cutting, pre-processing, frozen nano silica abrasive preparation and polishing and other aspects of the ice tray, wherein the pre-processing of the single crystal GaAs chip mainly includes two parts of the grinding and free abrasive chemical mechanical polishing, the main work done and The results achieved include: 1. single crystal gallium arsenide chip cutting process, the cutting process the midline speed and feed speed slice surface quality. When the feed rate is smaller, improving the cut line speeds can significantly increase the surface roughness of the single crystal GaAs film; When the feed rate is large to increase the line speed has little impact on the surface roughness of the sheet of monocrystalline GaAs . 2. Free abrasive chemical mechanical polishing of monocrystalline gallium arsenide chip technology, the use of the the SiO2 polishing slurry of the PH value of 9 to 11.5, and a pressure of 0.08MPa, the surface roughness of 8.0 nm; when the pressure is increased to 0.1MPa, surface roughness 7.81nm; surface roughness achieved when the pressure continues to increase 0.2MPa to 9.15nm. Vickers hardness tester indentation experiments on single crystal gallium arsenide chip, the temperature of the brittle-ductile transition mechanism of single crystal gallium arsenide chip. Below a 0.244N the small load zone, the hardness of a single crystal GaAs chip is increasing as the load increases, and no cracks; higher than the a 0.244N large load zone, GaAs chip The hardness with the increase of the load decreases, along with the generation and propagation of the crack. 4. The polishing liquid formulations used in the preparation of the ice tray is mainly including the nano silica polishing liquid dope, deionized water, deionized water and the nano-silica abrasive polishing liquid dope ratio in accordance with a ratio of 3:1, with H2O2 will The PH value was adjusted to between 9.5 to 10.5, and the nano silica concentration of about 10% in the polishing solution, the polishing solution of the prepared polishing effect of the ice tray. 5 using the method of the open mold and layered frozen freeze nanometer silicon oxide abrasive ice tray, significantly reduce the internal stress of the ice tray in the freezing process, cracks, bubbles, and the content of impurities; while using a transparent quartz glass polishing jig and UV adhesive curing, and improve the quality of the polished surface. 6. The ice tray Polishing monocrystalline GaAs film experimental process, using the ambient temperature of 10 ± 0.5 ° C, spindle speed of 100rpm, eccentricity of 50mm, the polishing pressure is 0.1MPa, it is possible to obtain an average value of the surface of 5.71nm roughness, and the surface roughness value of the center than the edges of the surface roughness values ??is small, the edge of a three-point average roughness value of 6.39nm, a three-point average roughness of the center value of 5.01nm.