Metal impurities unintentionally introduced into si wafers during various device process steps are very harmful to device performances . many gettering techniques have been widely studied to overcome these problems by removing metal impurities from the active region of a device . reduction in device size and introduction of new moralization processes require more efficient gettering techniques working at lower temperatures 半导体工艺中无意引入的金属杂质的污染会极大损害器件性能，为了将金属杂质从器件的有源区吸除，吸杂技术被广泛的研究，器件尺寸的不断缩小和新的金属化工艺的不断出现更需要能在低温有效吸除的技术。
Some previous experiments have showed that cavities had more efficient gettering than p - diffusion , mechanical damage and ion implantation . most of studies about cavities gettering are concentrated on the peculiarity of cavities gettering metal impurities intentionally into silicon wafer from the viewpoint of basic study . this technique especially applied to low - contamination process , how ever , has not been carefully studied , which should be important to the semiconductor manufacturing 而过去的工作多集中在从基础研究的角度研究氦微孔对有意掺入金属杂质的硅片的吸除特性，对无意引入的低浓度金属杂质的器件吸杂效果的研究却非常少，这方面的研究是氦微孔技术走向实际应用的必经之路。
In order to verify the effectiveness of steep - front impulse voltage test in finding the internal faults of composite insulator , some insulators with faults , including conductive channel , semi - conductive channels , airy channel , partial little air bubble that occur separately at different place , are modeled . steep - front wave impulse voltage test is made for these faulty insulator and normal insulator 为了检验陡波试验对于发现合成绝缘子内部故障的有效性，分别模拟了绝缘子内部不同部位有导电性、半导电性通道，小气泡，金属杂质，长气泡以及芯棒与护套间不粘连故障的绝缘子，并从三维静电场计算和用不同陡度的陡波试验两个方面进行了验证。
