铟磷共掺杂p型氧化锌薄膜形成机理和性质

利用射频磁控溅射在石英衬底上生长出铟磷共掺氧化锌薄膜(ZnO ∶ In,P),所用靶材为掺杂五氧化二磷(P₂O₅)和氧化铟(In₂O₃)的氧化锌(ZnO)陶瓷靶,掺杂质量分数分别为1.5%和0.3%,溅射气体为Ar和O₂的混合气体。原生ZnO薄膜是绝缘的, 600 ℃退火5 min后导电类型为n型,而800 ℃退火5 min后为p型。p型ZnO薄膜的电阻率、载流子浓度和霍尔迁移率分别为12.4 Ω·cm, 1.6×10¹⁷ cm^-3 和3.29 cm²·V^-1·s^-1。X射线衍射测量结果表明所有样品都只有(002)衍射峰,并与相同条件下生长的未掺杂ZnO相比向大角度方向偏移,意味着In和P都占据Zn位。XPS测试结果表明在共掺ZnO薄膜中P不是取代O而是取代Zn。因此,铟磷共掺ZnO薄膜中,In和P都取代Zn,并且P_Zn与2个锌空位(V_Zn)形成P_Zn-2V_Zn复合受主,薄膜表现为p型。

Formation Mechanism and Properties of In,P Codoped p-type ZnO Thin Film

In,P codoped ZnO ZnO∶(In,P)] films were grown on quartz by radio frequency magnetron sputtering,the ZnO target was mixed with 1.5% P2O5 and 0.3% In2O3,and the mixing gas of Ar and O2 was used as the sputtering gas.The as-grown ZnO∶(In,P) film shows insulating conduction,but n-type conductivity after annealing at 600 ℃ for 5 min,and p-type conduction after annealing at 800 ℃ for 5 min.The p-type ZnO:(In,P) has a resistivity of 12.4 Ω*cm,a carrier concentrativity of 1.6×1017 cm-3 and a Hall mobility of 3.29 cm2*V-1*s-1 .XRD mea-surement indicates that both the as-grown and annealed ZnO∶(In,P) films have a preferred (002) orientation and larger (002) diffraction angles than that of undoped ZnO prepared at the same conditions,implying that both In and P occupy Zn site in the ZnO∶(In,P).The XPS result confirm that the P substitutes Zn site (PZn) but not O site in the ZnO∶(In,P).Therefore,it was suggested that both In and P substitute at Zn sites in the ZnO∶(In,P) and the PZn combines with two Zn vacancies(VZn) to form a PZn-2VZn acceptor complex,which is responsible to p-type conductivity of the ZnO∶(In,P).