Abstract
We carry out the Cs, O activation experiment of AlGaN photocathodes and find the photocurrent is different from that of AlGaAs in the Cs, O coadsorption stage of activation. This is mainly due to there are dimers and trenches on the surfaces of AlGaAs photocathodes, and they provide enough position for Cs, O atoms to attach. Then pure surface model and the other two defect surface models with Ga or N vacancy are built. The result shows that the work function on the defect surface will have a significant decline at the stage of O adsorption. Thus, the photocurrent of AlGaN with defect surface will increase obviously at the second activation stage which is consistent with our experiment.
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Acknowledgements
This work was supported by the National Natural Science Foundation of China under Grant Nos. 61775203, 61308089 and 6144005, the National Key Research and Development Program of China under Grant No. 2017YFF0210800. The work was also supported in part by the National Science Foundation of the United States under Grant ECCS-1254902. We particularly appreciated Meishan Wang of School of Information and Electrical Engineering, Ludong University for first principle calculations.
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Liu, Z., Chen, L., Zhang, S., Meng, Q., Gu, Z., Hua, J. (2020). Experimental Research and Theoretical Study of Cesium, Oxygen Activation on Defect AlGaN (0001) Surface. In: Peng, Y., Dong, X. (eds) Proceedings of 2018 International Conference on Optoelectronics and Measurement. Lecture Notes in Electrical Engineering, vol 567. Springer, Singapore. https://doi.org/10.1007/978-981-13-8595-7_17
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