High mobility ultrathin ZnO p–n homojunction modulated by Zn0.85Mg0.15O quantum barriers
Yang Jing-Jing1, 2, Fang Qing-Qing1, †, Du Wen-Han2, 3, ‡, Zhang Ke-Ke3, Dong Da-Shun1
       

The four-probe method used for Hall effect test.