| This paper studies the defect control and optimization issue of the BPSG process.Though studies the various defects problems of BPSG in the growth process, wefound out a solution and achieve the effective control. Specific contents are asfollows:1. The application of BPSG and the problem of prone to defects in the process.As the first metal front dielectric layer (PMD) and metal interlayer dielectric(IMD), BPSG has been widely used in IC manufacturing. But various defects willappear in the process of CVD, the defects will affect the nature of the BPSG andcause wafer yield reduced greatly or wafer scrapped.2. The principle of prone to defects in BPSG and its effect.There are many reasons could cause the defect issue of BPSG, including thehardware and the process. The types of defects including the thickness, particles,evenness and boron phosphorus content, etc. In this paper, the different causes andtypes of the defects will be analyzed.3. The defect control of BPSG.Based on all kinds of reasons, we take the corresponding measures to achieve thegoal of inhibit or decrease defect as far as possible. We are usually throughprocess improvement to adjust B, P content in an optimum range, to avoid thedefect of B, P content; through the optimization of the program to avoid the defectthat caused by the precipitation of P. By optimizing the setting of production tool,regular maintenance and control the related parameters to ensure that the chamberand the whole machine achieve a good environment. Specifically, for improve thethickness of the film, particles and evenness defects that may occur, we needensure that all gas, temperature and pressure are within the set range. |
