Planarizing Deposited SiO2 Thin Films Using ISSG Annealing Technology
利用ISSG退火技术实现沉积二氧化硅薄膜平坦化

Due to the reaction vapor concentration gradient in LPCVD furnaces,as-grown oxide films tend to be thinner at the wafer edge than at the wafer center.ISSG (in-situ steam generation) annealing,a new low-pressure rapid oxidation annealing technique,is used to compensate this non-uniformity in thickness from oxide deposition and obtain uniform SiO2 thin films.Experimental data show that the variation of the oxide thickness (between the maximum and the minimum) is reduced from 0.76 to 0.16nm,and the standard deviation for 49 points is reduced from 0.25 to 0.04nm.The ISSG-annealed oxide films,with a tunneling electrical field improved to 4.3MV/cm,also show better interface quality than those annealed by conventional O.2.The results provide a convenient and effective solution for planarizing deposited SiO2 thin films for VLSI manufacture