Defect Principle and Improvement of 28nm Germanium Silicon Epitaxial Growth Process

With the characteristic size of integrated chip entering 28nm, selective epitaxy technology of silicon germanium (SiGe) has become an indispensable key technology. Although this technology can improve the performance of PMOS devices, the degree of improvement is closely related to the defects of the devices. These defects are not only related to the epitaxial process itself, but also directly related to the process integration, which will affect the defect detection of the subsequent multi-channel process, as well as the yield and reliability of the device. Major defects, such as tiny particle defects and insufficient germanium and silicon growth, are major killers that affect device output. In this paper, these defects are studied in detail, the formation mechanism are discussed and the corresponding solutions are put forward.