【作者】 张建峰；

【导师】 刘彩池； 周旗钢；

【作者基本信息】 河北工业大学 ， 材料物理与化学， 2004， 硕士

【摘要】 本文研究了大直径直拉硅单晶中的原生微缺陷—流动图形缺陷（flow pattern defects，FPDs）。分析了FPDs的微观形貌，及其在Secco腐蚀液中的演变过程；对轻掺B、重掺Sb硅片在Ar，H₂，N₂，N₂／O₂（3％）不同气氛下进行高温快速退火（RTA），研究了FPDs的高温退火行为及减少FPDs的快速退火工艺。 实验结果表明：FPDs外部轮廓为抛物线型，内部存在台阶结构。利用原子力显微镜观察发现位于FPDs端部的空洞结构有单型和双型两种类型，并首次发现空洞两侧有对称凸起结构。提出了一个抛物线模型，首次对FPDs在Secco腐蚀液中的演变过程进行了合理的解释。 硅片经1100℃以上高温RTA处理后，FPDs明显减少，其密度随着退火时间的延长而不断降低。高温RTA处理过程中FPDs端部空洞微结构发生变化，本文对其湮灭机理进行了详细探讨。氢气高温RTA处理，是减少FPDs的最有效退火工艺，氨气次之。 首次对大直径重掺Sb硅片中的FPDs进行了研究。重掺Sb硅片中FPDs密度比轻掺B的高出一个数量级；在经过相同工艺处理后，重掺Sb硅片中FPDs密度明显降低，且降低幅度大于轻掺B硅片。硅中大量Sb原子的掺入，影响了氧的行为，进而影响了原生微缺陷的分布及退火行为，具体的影响机制有待于进一步研究。更多还原

【Abstract】 In this paper, the microstructure of flow pattern defects (FPDs), one kind of grown-in micro-defects, in large-diameter as-grown CZ-Si single crystals was investigated. The microstructure of FPDs was analyzed and the evolution of FPDs during Secco etching procedure was also studied. Furthermore, the lightly B-doped and heavily Sb-doped CZ-Si wafers were treated by rapid thermal annealing (RTA) technique in Ar, H2, N2, N2/O2 (3%) respectively at high tempretures. The behavior of FPDs during RTA process and the effective RTA process to decrease the density of FPDs were discussed in detail.The experimental results showed that the outline of FPDs is parabola, and several steps exist in the inner part of FPDs. There are two kinds of voids on the tip of FPDs observed by atomic force microscope (AFM), one of which is single and the other is dual type. Two heaves are firstly found on the left and right sides of the void. Moreover, a parabola model was put forward to explain the evolution of FPDs in CZ-Si wafers during Secco etching procedure firstly.After RTA treatment at 1100 C or even high tempretures, the density of FPDs decreased obviously and decreased successively with the annealling time increasing. The microstruture of the void on the tip of FPDs changed during RTA process, and the annihilation mechanism was discussed in this paper. The RTA treatment in H2 atmosphere was the most effective annealling process to decrease the density of FPDs, and RTA in Ar atmosphere takes second place.The FPDs in large-diameter heavily Sb-doped silicon wafers was investigated firstly. The density of FPDs in heavily Sb-doped silicon wafers was 10 times or so higher than that in lightly B-doped silicon wafers. After RTA treatment, the density of FPDs decreased too. The difference between them was that the FPDs in Sb-doped wafers was more easily eliminated than that in lightly B doped wafers due to the effects of the high concentration of Sb, which strongly effected the behivior of oxygen in silicon. The mechanism needs to be investigated later.更多还原