Logic Device Side Wall Etching Study

We are undergoing a new technological revolution and the driving force of it is the continuous development of the semiconductor industry which promoted by the development of semiconductor's design and manufacturing process innovation. Now the international semiconductor manufacturing process has stridden into the nanotechnology era and the several world-class manufacturing giants can mass-produce the IC with the line width of 32nm and the line width is shrinking now. Presently, most of Chinese mass foundry's production lines are 8-inch lines of 0.13um manufacturing process and the 12-inch lines are with 65nm manufacturing process. But with the aging foundry's equipment, more and more new problems arise in the foundry. The thesis is about the Spacer etching's problems including three sections based on the 8-inch line and 0.13um Process.Firstly, it is about the 0.13um process and the equipment for Spacer etching. The principles of Spacer etching in 0.13um process and Spacer etching method, especially for Spacer structure, will be presented in detail. And the silicon nitride and silicon oxide etching will be studied in-depth. Then there will be a detailed analysis about the Spacer etching's equipment "Super E", including the device's structure and the characteristics of its components.Spacer etching's defect is a major killer for the yields and we will study it to find the root cause to resolve it. First, we will do the research of the defect related with equipment including the parts and the vacuum system, etc. But the relationship is not obvious. Using the orthogonal experimental method to analyze the process parameters which affect the defect by etching step in the recipe, we eventually found that the aging vacuum system and the etching process step were the major factors for the defect.Lastly, there will be research about the spacer etching's remained oxide control. This is a remained oxide layer after spacer etching and the layer is the main mask layer for the latter ion implantation. The ion implantation is very sensitive to the thickness of the layer. By orthogonal experiment, we find out the oxygen is the major factor that affect the remained oxide's thickness. But it will lead to WAT fail if we adjust the flow of the oxygen in the recipe. We will also study the relation between the remained oxide thickness with the chucking voltage, temperature and magnetic fields. The remained oxide thickness will be thicker with the higher temperature and the higher temperature does not affect other properties. Therefore, we adjust the process temperature to control thickness of the spacer remained oxide.There is a reasonable explanation about spacer's defect including how to reduce the defect and a better adjustment method to control the remained oxide's thickness. People can refer to the thesis to solve the similar problems that arise with the aging equipment in other foundries.