Development Of Polish Head Test Station For Chemical Mechanical Polishing

Chemical-Mechanical Planarization(CMP), as the ideal way to achieve overall and part planarization simultaneously, is used to remove materials by dual action of chemical and mechanical effects, providing surface with high quality level.At present a typical dry-into and dry-out CMP device usually consists of polishing system, in-position detection system, cleaning system, drying system as well as robot handling system etc, in which polishing system is regarded as the core of CMP. As the key part of polishing system, the detection platform of polishing head plays an important role in uniformity of polishing quality, which reduces maintenance time of CPM device and improves efficiency of CPM.In accordance with process practice requirements and related abroad research, it is required to detect loading and unloading pieces of polishing head. Series of mechanical structures are designed to measure height, deviation etc. of the pieces all around, providing data for design of CMP device.In accordance with process practice requirements and related device research in semiconductor industry, it is necessary to select relative cleaner power energy resources--air-pressure drive. With the help of gas circuit configured by related pneumatic component, it is reliable to do the detection tasks, providing detection platform for changing and maintenance of polishing head.In accordance with process practice requirements and related research about CMP, requirements of pressure control for polishing head emerges. By analysis of different PID control algorithm, including general PID control algorithm, integral separation PID algorithm, variable speed integral PID and simulation comparison, the variable-speed integral algorithm is considered as the perfect way to control pressure of polishing head. Besides PID parameter in the pressure control system of CMP polishing head has been set.In the process of process demands, scheme plan, drawing design, production and processing and final practice test for platform, the ultimate target is to detect indicators of polishing head by detect platform. The practice data make it clear that, such platform has achieved high performance level for detection of process indictors, playing an important role on design and maintenance of CMP device.