second breakdown meaning in English

第二次击穿
二次击穿

And the results of calculation and numerical simulation indicate , without increasing the intrinsic collector - junction area of power devices , collector - combed structure helps to raise the intrinsic heat - dissipating area and base ' s perimeter , improve heat - dissipating method of each cell of the chip , enhance the distribution uniformity of junction temperature and current of each cell of the chip , reduce the thermal resistance and raise the dissipation power pd and output power p0 , fairly well relax the contradiction among frequency , out - put power and dissipation power of the devices , and further improve the devices " property against second breakdown
而计算分析和二维数值模拟分析结果表明：梳状集电结(基区)结构在不增加器件本征集电结面积的条件下，增大了器件的本征散热面积和基区周长，改进了每个子器件单元内的散热方式，提高了单元内结温和电流分布的均匀性，降低了器件的热阻，增大了器件的耗散功率和输出功率，较好地缓解了目前传统结构中频率与功率、功耗的矛盾，并有利于改善器件抗二次击穿的性能。