Development of a High Quality-factor Micro Spiral Inductor

• Main Authors: Chin-hao Tu, 塗謹豪
• Other Authors: I-Yu Huang
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/41563035899587585640

碩士 === 國立中山大學 === 電機工程學系研究所 === 103 === In order to reduce the power consumption of portable electronic devices, this thesis aims to develop a high quality-factor micro spiral inductor for DC-DC converter applications. According to the published literatures, the quality-factor of conventional spiral inductor is only about 2~4.5 as it operated at low frequency (e.g. 100 kHz~1 MHz). Such low quality-factor will result in high power consumption. In this research, the influence of five geometric parameters of the proposed micro spiral inductor on the quality-factor are investigated and a high quality-factor (Q&;gt;6) can be achieved utilizing ANSYS Maxwell commercial simulation software and micro-electro-mechanical systems (MEMS) technology. The simulated inductance and resistance of the proposed micro spiral inductor are increased and decreased respectively as the diameter and thickness are increased, therefore, the quality-factor can be effectively increased. Besides of the diameter and thickness parameters, the influence of the coil width, coil space and number of turns on the quality-factor of the proposed micro spiral inductor also will be discussed. A maximum simulated quality-factor (Q=6.92) can be obtained in this work as the five geometric parameters are optimized. After three thin-film deposition and one photolithography fabrication processes, fifteen micro spiral inductors with different geometry designs are implemented and characterized. In this thesis, a high quality-factor (Q=6.07) measured at 1 MHz can be demonstrated as the presented micro spiral inductor with 5000 μm-diameter, 74.45 μm-thickness, 60 μm-coil width, 10 μm-coil space and 15-coil turns. All of the simulated and measured results are match very well with the theoretical prediction.