Comparison of magnetic property of Cu-, Al-, and Li-doped ZnO dilute magnetic semiconductor thin films

Abstract

The properties of Cu-, Al-, and Li-doped ZnO dilute magnetic semiconductor (DMS) have been analyzed and compared. Zincite with wurtzite structures have been synthesized successfully on SiO"2 (101) and SiO"2 (110) substrates in both the CuZnO and LiZnO DMS. The highly textured ZnO (002) peaks were able to form in the CuZnO system at 400°C. However, it formed at even much lower temperature in the LiZnO system, that is only 25°C. ZnO (002) peaks in both systems were formed without any impurity phases. However, no crystalline structure is synthesized in the AlZnO system. The thin films formed are amorphous. The structural and related magnetic properties of the films were analyzed by XRD, AFM, and VSM. The films were found to be at their highest magnetism at the value of 3.1 emu/cm3 for CoZnO and 2.5 emu/cm 3 for LiZnO, synthesized at 400°C, and under 1 × 10 -4 Torr oxygen partial pressure. © 2008 World Scientific Publishing Company.