0.35μm BCD Process Flow Improvement And Optimization

BCD technology(BIPOLAR/CMOS/DMOS) incorporates BIPOLAR、CMOS andMOS on one chip. The essential advantage is that designers can select freely betweendevice of high-resolution analog BIPOLAR、high-integration CMOS and high-PowerDMOS. BCD technology can be used widely in Power Management IC. With thegrowing informationization and green power conservation in China, and intelligentPower Grid and intelligent industry, domestic Power Management market is foreseeableto grow rapidly. Under that background, Texas Instrument Chengdu company investedthe development of0.35μm BCD technology to meet the market and get morecompetent in it.The work of this thesis goes through the development of0.35μm BCDtechnology of the company and encounters a series of process problems, such as inPHOTO, WET Clean, RTA and Metal Interconnection and etc. Based on the processproblem met during work, improvement work on key process parameters have beenfinished for the main device LDMOS and NPN BJT, accordingly the whole0.35μmBCD process flow has been improved suitable for production.The main contents are as follows:1．N+/P+SD process flow loop development and improvement for LDMOS device,including N+/P+SD PHOTO process, N+/P+SD Ion Implantation process, N+/P+SDClean process post Ion Implantation, process defect scan and detect based on problem ofN+/P+SD pillar-pattern Photo resist peeling.2．Related process flow loop development and key process improvement for NPNBJT device, including related process introduction, process fail model analysis, thedesign and verification of CO SALICIDE experiment and RTA experiment post IonImplantation.3．Back-end process loop flow improvement for the solution of Metal relatedprocess problems, including Contact process loop flow improvement for Tungsten voidprocess problem solution and Via process loop flow improvement for Aluminum pitsprocess problem solution. 0.35μm BCD technology process baseline of the company was set up robustlythrough the improvement work on key process flow parameters in0.35μm BCDprocess based on device performance.