The Effect of Oxygen Adsorption on the Depth of Space Charge Region on ZnO (1010)

摘要

The apparent depth of space charge region on the ZnO (1010) surface in chemisorption of oxygen has been estimated from the capacitance of two contacting faces. When the sample (donor concentration: 2.4】1022 m-3) was evacuated at 773 K for 1 hr the depth reached to 40-100 ∈ depending on sample assembly. Admission of oxygen to the sample resulted in an increase of the depth to 3600 ∈ where the increment was greater at higher oxygen pressure between 6.6-1600 N/m2. Admission of CO to the sample previously exposed to oxygen yields a decrease in the depth. The results of the measurement support that oxygen is adsorbed as an acceptor on ZnO (1010).