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本文研究了I~2L和线性双极电路内吸除工艺对电路性能的影响。这种吸除技术是在工艺过程中通过控制氧在硅片中的沉淀而引入的。已测量出这种影响会使电路的漏电流减少,并反映到成品率提高。业已发现吸除效率是沉淀氧含量和沉淀物形貌的强函数关系。还发现这些因素影响了硅片的机械强度(翘曲度)。对于相对较低的沉淀氧含量(约10ppm),已得到所需要的沉淀物形貌,从而得到最佳的吸除和提高成品率。沉淀氧含量的增加会降低吸除效率,同时也会减小硅片的机械强度。本研究表明除了已知因素(例如纯净硅片中填隙氧浓度、双极工艺过程中氧沉淀动力学)外还受其它一些因素(如氧沉淀核化中心浓度等)的强烈影响。它们控制着氧沉淀速率和沉淀物的形貌。因为这些中心的浓度与晶体生长条件有关,所以我们发现:由不同厂家提供的硅片中,沉淀动力学是不同的。这就可能导致不寻常的后果。例如我们发现在有初始氧浓度为40ppm的硅片中沉淀氧含量比另外厂家所提供的硅片初始氧浓度28ppm或31ppm的硅片中沉淀氧含量更低。我们相信我们的结论清楚地证明:优化后的内部吸除工艺可用来提高双极型工艺线上的成品率。
In this paper, I ~ 2L and linear bipolar circuit suction process on the circuit performance. This suction technique is introduced during the process by controlling the precipitation of oxygen in the wafer. This effect has been measured to reduce the leakage current of the circuit and reflect the increased yield. Absorption efficiency has been found to be a strong function of the precipitated oxygen content and the morphology of the precipitate. It was also found that these factors affected the mechanical strength (warpage) of the wafers. For a relatively low amount of precipitated oxygen (about 10 ppm), the desired precipitate morphology has been obtained, resulting in optimal aspiration and increased yield. Increasing the amount of precipitated oxygen reduces the efficiency of aspiration and also reduces the mechanical strength of the wafers. This study shows that in addition to known factors (such as oxygen concentration in pure silicon interstitial oxygen, bipolar process of oxygen precipitation kinetics) is also strongly influenced by some other factors (such as oxygen precipitation nucleation center concentration). They control the oxygen deposition rate and the morphology of the precipitate. Because the concentrations of these centers are related to the crystal growth conditions, we found that precipitation kinetics are different among the wafers supplied by different manufacturers. This can lead to unusual consequences. For example, we found that the oxygen content of precipitated silicon in silicon wafers with an initial oxygen concentration of 40 ppm is lower than those of silicon wafers with an initial oxygen concentration of 28 ppm or 31 ppm provided by another manufacturer. We believe our conclusion clearly demonstrates that the optimized internal aspiration process can be used to increase the yield on bipolar process lines.