Electric Characteristic Enhancement of an AZO/Si Schottky Barrier Diode with Hydrogen Plasma Surface Treatment and AlxOx Guard Ring Structure

Chien-Yu Li; Min-Yu Cheng; Mau-Phon Houng; Cheng-Fu Yang; Jing Liu

doi:10.3390/ma11010090

Electric Characteristic Enhancement of an AZO/Si Schottky Barrier Diode with Hydrogen Plasma Surface Treatment and Al_xO_x Guard Ring Structure

Materials (Basel). 2018 Jan 8;11(1):90. doi: 10.3390/ma11010090.

Authors

Chien-Yu Li¹, Min-Yu Cheng², Mau-Phon Houng³, Cheng-Fu Yang⁴, Jing Liu⁵

Affiliations

¹ Institute of Microelectronics, Department of Electrical Engineering, National Cheng Kung University, No. 1, University Road, Tainan 701, Taiwan. q18021014@mail.ncku.edu.tw.
² Institute of Microelectronics, Department of Electrical Engineering, National Cheng Kung University, No. 1, University Road, Tainan 701, Taiwan. q16044082@mail.ncku.edu.tw.
³ Institute of Microelectronics, Department of Electrical Engineering, National Cheng Kung University, No. 1, University Road, Tainan 701, Taiwan. mphoung@eembox.ncku.edu.tw.
⁴ Department of Chemical and Materials Engineering, National University of Kaohsiung, No. 700, Kaohsiung University Road, Nan-Tzu District, Kaohsiung 811, Taiwan. cfyang@nuk.edu.tw.
⁵ School of Information Engineering, Jimei University, Xiamen 361021, China. jingliu@jmu.edu.cn.

Abstract

In this study, the design and fabrication of AZO/n-Si Schottky barrier diodes (SBDs) with hydrogen plasma treatment on silicon surface and Al_xO_x guard ring were presented. The Si surface exhibited less interface defects after the cleaning process following with 30 w of H₂ plasma treatment that improved the switching properties of the following formed SBDs. The rapid thermal annealing experiment also held at 400 °C to enhance the breakdown voltage of SBDs. The edge effect of the SBDs was also suppressed with the Al_xO_x guard ring structure deposited by the atomic layer deposition (ALD) at the side of the SBDs. Experimental results show that the reverse leakage current was reduced and the breakdown voltage increased with an addition of the Al_xO_x guard ring. The diode and fabrication technology developed in the study were applicable to the realization of SBDs with a high breakdown voltage (>200 V), a low reverse leakage current density (≤72 μA/mm²@100 V), and a Schottky barrier height of 1.074 eV.

Keywords: Schottky barrier diodes; atomic layer deposition; guard ring; hydrogen plasma; rapid thermal annealing.