针对KDP晶体生长过程中常出现的SO4^2-,NO3^-和Cl^-杂质,采用传统法和快速法掺杂生长了一系列KDP晶体,研究了不同阴离子杂质掺杂对KDP晶体X和Z向的电导率的影响。结果表明,X向的电导率比Z向电导率高;未掺杂时,快速生长的KDP晶体比传统法生长的KDP晶体具有更高的电导率;SO4^2-的掺杂增大了晶体在两个方向的电导率,且随着掺杂浓度的增加,晶体的电导率也相应增大;NO3^-和Cl^-对KDP晶体的电导率影响不大。分析认为,快速生长的KDP晶体具有更高的缺陷浓度,从而增大了晶体的电导率;SO4^2-具有与PO4^3-结构的相似性,从而能够取代部分PO4^3-进入晶格,从而产生H^+空位。H^+空位的定向移动能增大晶体的电导率。而NO3^-和Cl^-与PO4^3-结构差异较大,很难取代进入PO4^3-晶格,因此NO3^-和Cl^-对KDP晶体的电导率影响不大。
A series of KDP crystals were grown by traditional and rapid growth methods,doped with SO4^2-,NO3^-and Cl^-anions,which were commonly in existence during crystal growth process.The influence of different ion-doped on electrical conductivity of KDP crystals along Xand Zdirections were investigated.Experimental results implied that the electrical conductivity of KDP crystals grown by rapid method was higher than that by traditional method without any doping,and along Xdirection,the electrical conductivity is higher than along Zdirection as well.Additionally,along Xand Zdirections,the electrical conductivity increased as the SO4^2- doping content increasing,while NO3^- and Cl^-had little contribution to electrical conductivity.Taking the structural similarity of SO4^2- and PO4^3- into account,SO4^2- could enter KDP crystal lattice and replace PO4^3-,which resulte in H^+ vacancy.The directional migrations along both Xand Zdirections of H^+ vacancy could enhance the electrical conductivity of KDP crystal.Owing to the structural dissimilarity of NO3^-and Cl^-to PO4^3-,it was difficult for NO3^- and Cl^-to replace PO4^3-,which resultes little contribution to electrical conductivity.