不同掺锗浓度对多晶硅性能的影响

Influence of Different Germanium Doping Concentration on the Performance of the Multi-crystalline Silicon

研究不同的掺锗浓度对硼掺杂P型多晶硅铸锭性能的影响。实验结果表明:掺锗能够影响多晶硅铸锭中的位错密度、间隙氧浓度和硅片的机械强度。当掺锗浓度低于5×1019 at·cm-3时,位错密度和间隙氧浓度随着掺锗浓度的增加而降低,机械强度则随着掺锗浓度的增加而增强。当铸锭中掺锗浓度为5×1019 at·cm-3时,与不掺锗的硅片相比,掺锗硅片中位错密度平均降低约3%,间隙氧浓度平均降低约6%,机械强度平均提高约20%。但是,当掺锗浓度高于1×1020 at·cm-3时,掺锗对多晶硅铸锭性能的改善效果变差了,并对其性能产生不利的影响。

The influence of different concentrations of germanium （Ge） doping on the performance of boron doped p-type multi-crystalline silicon （mc-Si） was investigated.The results showed that doping Ge in silicon could affect dislocation density,interstitial oxygen concentration and the mechanical strength of silicon wafers.When the Ge concentration was lower than 5 × 10^19 at ·em^-3,dislocation density and interstitial oxygen concentration were reduced and the mechanical strength was improved with increasing Ge concentration.When the Ge concentration was 5 × 10^19 at · cm^-3,in the Ge-doped silicon wafers,the average dislocation density and the interstitial oxygen concentration was reduced by 3% and 6%,and the average mechanical strength was improved by 20% in comparison with un-doped ones.However,when the Ge concentration was as high as 1 × 10^20at · cm^-3,the effect of Ge doping on these performances of the mc-Si was weakened,so that Ge doping in silicon was of no benefit to its performance.