Investigation of silicon-on-insulator (SOI) technology by plasma immersion ion implantation (PIII)

Abstract

Plasma immersion ion implantation (PIII) is a novel technique and has a number of advantages over conventional line-of-sight implantation techniques. Its applications include surface modification of industrial components, biomaterials characterization, impurities doping, formation of shallow junctions, production of flat panel display and synthesis of silicon-on-insulator (SOI) materials, and so on. PI11 continues to be an area attracting much attention and much work is focusing on the optimization of operation conditions. In this work, theoretical and experimental studies are conducted on several aspects especially those pertaining to semiconductor applications. The plasma source discharge efficiency, plasma transportation phenomena, and the effects of external magnetic field on the discharge, ion transportation, as well as implantation efficiency are discussed in Chapter 2. The feasibility of long pulse PI11 is investigated. The main concept includes separating the vacuum chamber into two parts by a conducting grid. Comparison of long-pulse PI11 with short-pulse and direct current (DC) PI11 is described in Chapter 3. Direct-Current (DC) PI11 is also explored and applied to the fabrication of SO1 materials by means of hydrogen implantation and ion-cut. The DC mode exhibits a number of advantages in treating planar Si wafers such as the reduction of contamination, defect formation, and surface hydrogen absorption. Grid biasing is investigated and the enhanced implantation efficiency and uniformity using a multipolar ECR source is discussed in Chapter 4. In Chapter 5, substrate damage and contamination in hydrogen PI11 are discussed, including theoretical and experimental studies to alleviate damage and contamination. Chapter 6 covers the conclusion and suggests future work.