高温退火气氛对Denuded Zones的影响

由DZ宽度与退火时间和温度的关系曲线,测定了含氧硅在N_2、O_2、O_2~+5％HCI气氛中退火时硅中间隙氧的外扩散激活能。实验表明:在氧化气氛中退火,有利于原始硅片中潜在微缺陷的消除和推迟间隙氧的沉淀,增强间隙氧的外扩散,可获得较宽的DZ.

THE EFFECTS OF AMBIENT IN HIGH TEMPERATURE ANNEALING ON DENUDED ZONES

In this paper, the effects of heating temperature, time, and ambient on denuded zones in high oxygen silicon wafers are investigated with wright etchant and optical microscope. The out-diffusion activation energies of the interstitial oxygen in N2, O2, O2+5%HCl ambients are 2.4eV, 1.4eV, 1 .1eV,respectively. The exponent of time measure d is about 0.5 for three different ambients.These results show that high temperature annealing in O2+5%HCl ambient can annihilate the jatent microdefect of silicon wafers, retard precipitation of interstitial oxygen enhance out-diffusion of the interstitial oxygen, thus even wider DZ can be obtained.