Papers by Author: Xiao Zhen Hu

Abstract: Through deeply research and analysis the extruding technology of PVC crusting-foam plate, several main equipments of the production line system such as extruder power transmission system, machine barrel, screw, cooling stereotypes system and traction cutting system are designed. The drawings of all components and parts are drawn by using AutoCAD and Pro/E soft. After the production line assembled, some related experiments, measurement and analysis are completed, and the results show that the quality of PVC plates produced by our production line attained to technical level of imported products.

Abstract: This study compares the effectiveness of different polishing slurries for Double Sided Polishing process of Silicon wafer in the polished surface roughness and stock removal rate, discusses the mechanism of Double Sided Polishing for silicon wafer with different type slurries, also the influence of the pH value, temperature and concentration of the slurries are discussed in this paper. Furthermore, by the optimization of the process parameters, the ultra-smooth of polished surface of silicon wafer has been got with higher efficient.

Abstract: Based on the kinematic analysis of the double sided polishing process, the equation of relative velocity (the workpiece to the polishing plate) is established. According to the Preston’s equation, the function of stock removal uniformity is presented. By computer simulations of the machining process, the effects of rotating speed ratios (the carrier revolution speed to plate rotating speed, carrier rotating speed to plate speed) on the stock removal uniformity are discussed in this paper. At last, some experiments have been done for validating the theoretical study of stock removal uniformity. The results show that, the computer simulation can estimate and conduct the experiment result in double-sided polishing process.

Abstract: Nanometer K0.6Sr0.7Zr4P6O24 (KSZP) powders were synthesized from KNO3, Sr(NO3)2, NH4H2PO4 and ZrOCl2·8H2O by a direct co-precipitation method. The as-prepared precipitates and KSZP powders were characterized by thermal analysis, X-ray powder diffraction, granulometer and scanning electron microscope. The crystallization and particle characteristics of the KSZP powder product depend on treatment temperatures and the nanometer KSZP powder can be attained after heat-treated at 900°C. The effects of the sintering conditions on the densification of nanometer KSZP powder and the properties of KSZP ceramics were studied. Under the sintering temperature of 1380°C and the sintering time of 2h and the additive of Nb2O5 2wt%, the KSZP ceramic from the nanometer powder after heat-treated at 900°C has better comprehensive properties.

Abstract: Double sided polishing process has become a main machining method for silicon wafer finishing process, but it is difficult to get ultra-smooth surface with the very stringent machining conditions. In this paper, the mechanism of ultra-smooth surface machining process was studied, the main parameters affecting the surface quality of silicon wafer, such as the polishing pad and carrier rotation speed, polishing press, polishing slurries etc. , were discussed and optimized, then ultra-smooth surface of silicon wafer with Ra 0.4nm has been obtained based on the above study. A new double sided polishing machine with computer control system equipped with a digital controlled press valve was developed, and the ultra-smooth machining process of silicon wafer was established in this paper.

Abstract: The functional materials such as sapphire, silicon wafer etc. are processed efficiently with ultra-smooth surface for the demand of the rapid development of the IC industry. The precise double sided polishing process is one of the main methods of getting the ultra-smooth surface for these materials. This paper introduces the structure and characteristic of the precise double sided polishing machine with a precise pressure control system equipped a new type electro-pneumatic digital servo valve. The works, such as machine design, development of the control system and optimization of process parameters etc. are carried out to meet the requirement of the precise double sided polishing machining process. This equipment has the characteristic of high machining precision and precise control capability, so it can be applied to the ultra-precise machining of the ultra-thin sapphire, silicon wafers etc.