International Journal of Engineering and Technical Research (IJETR) ISSN: 2321-0869, Volume-2, Issue-10, October 2014 141 www.erpublication.org Abstract — This paper presents the design and implementation of a high-performance, compact Wilkinson power divider using an optimized integrated passive device fabrication process on a GaAs substrate for LTE application. Compared to the previous integrated passive device processes, this optimized fabrication process is developed to further reduce the fabrication time and total fabrication cost and to greatly increase the RF performances. The optimized processes are demonstrated and several key parameters are compared for the previous process and optimized process in detail. A Wilkinson power divider is realized using this proposed manufacturing process and is packaged using the SOT-26 packaging method, which shows excellent RF performances with a compact size and low cost. The bare-chip measurement results show two insertion losses below 3.35 dB/ 3.40 dB, all return losses of greater than 15.20 dB and an isolation of greater than 38.00 dB. The measured insertion losses for the packaged power divider are better than 3.50 dB/ 3.50 dB, all return losses of greater than 13.50 dB and an isolation of greater than 26.20 dB around the desired frequency. The operating frequency is between 2.24 GHz and 2.40 GHz, which is the LTE application frequency range of band 40. The reliability of the MIM capacitor and power divider is investigated by using a highly accelerated stress test, which results indicate that both the component and device fabricated by the optimized process have a stable and reliable performance. Index Terms— High Performance, IPD Process, LTE Application, Wilkinson Power Divider. I. INTRODUCTION Conventional Wilkinson power dividers are widely used in radio frequency (RF) front-end communication systems for equal/unequal power splitting with in-phase responses at different output ports. Recently, researchers reported several novel power dividers for facilitating the system integration and simplifying the architecture of the RF front-end [1-6]. However, these transmission line-based power dividers on the printed circuit board occupy a large chip area, increase the cost and incur additional power consumption capabilities. Therefore, the development of a high-level integrated fabrication process for the power divider is an important task with the aim of obtaining a compact size and low loss. Integrated passive devices (IPDs), which contain passive circuit components such as resistors, inductors, and Manuscript received October 17, 2014. E. S. Kim, Deportment of Electronics, Kwangwoon University, Seoul, South Korea, 82-10. Y. Li, Deportment of Electronics, Kwangwoon University, Seoul, South Korea. Z. Yao, Deportment of Electronics, Kwangwoon University, Seoul, South Korea. N. Y. Kim, Deportment of Electronics, Kwangwoon University, Seoul, South Korea, 82-10, Corresponding Author. capacitors, can be totally integrated and mounted on a semiconducting substrate [7-8]. Through IPD technology, it is possible to integrate individual passive components into an RF device or system [9]. IPDs can be applied to existing fields of applications, which use whole passive devices, and have already been applied to the front-end modules (FEMs) of mobile systems. In addition, in mobile phone communication systems, other functional blocks such as filters, baluns, diplexers, directional couplers, transformers, and power dividers/combiners can also be realized by using IPD technology [10-14]. In this work, a GaAs-based fabrication process that enables the integration of discrete passive components on an IC is considered. This method is highly competitive in terms of its reliability, cost, and yield. A few years ago, we developed a fabrication process for IPDs that consisted of thin film resistors (TFRs), spiral inductors, and metal-insulator-metal (MIM) capacitors with only six layers [15-16] and we continue to improve this previous fabrication process. Currently, this process has been modified to develop a more reliable, cost effective and higher RF performance fabrication process. These optimizations consist of the modification of the bottom metal fabrication processes from the semi-additive method to the subtractive method, the improvement of the bottom metal smoothness, the adjustment of the air-bridge metal thickness, the use of the sputter-etching process, and the use of the SU-8 photoresist as a final passivation. Additionally, several integrated passive components are fabricated using both the previous process and the optimized fabrication process and these two types of IPD fabrication processes are compared by using these components in view of the measurements. A compact Wilkinson power divider is proposed as a result of this optimized IPD manufacturing process. The Wilkinson power divider is designed and implemented and has very good RF performances with a very compact size. On the other hand, packaging determines the reliability and long-term stability of a microwave device, and good packaging is essential for its commercial success. Therefore, the fabricated power divider was finally packaged using the SOT-26 packaging method and was analyzed. The reliability of the MIM capacitor and packaged power divider was investigated by using highly accelerated stress test. The reliability experimental results indicate that both the component and device fabricated by the optimized process have a stable and reliable performance. A Compact Wilkinson Power Divider with High Performance by GaAs-based Optimized IPD Process E. S. Kim, Y Li, Z. Yao, N. Y. Kim