Electron. Mater. Lett., Vol. 13, No. 3 (2017), pp. 230-234 230 Radiofrequency Characteristics of Ionized Sputtered Tantalum Nitride Thin-Film Resistor in CMOS Device Woo Suk Sul, 2 Soon Hyeong Kwon, 1 Eunmi Choi, 1 Yinhua Cui, 1 Kang Won Lee, 1 Ho Jae Shim, 1 Yuan Gao, 1 Sang June Hahn, 3 and Sung Gyu Pyo 1, * 1 School of Integrative Engineering, Chung-Ang University, Seoul 06974, Korea 2 National NanoFab Center (NNFC), Daejeon 34141, Korea 3 Department of Physics, Chung-Ang University, Seoul 06974, Korea (received date: 15 November 2016 / accepted date: 25 January 2017 / published date: 10 May 2017) 1. INTRODUCTION Owing to the dramatic development of portable wireless devices, radiofrequency (RF) devices must satisfy extensive requirements, including minimization, high performance, lightness, and low power and cost. [1] Many studies are being conducted on integrated circuit-based elements for satisfying these requirements. [2-5] Si-based RF integrated circuits (RFICs) are commonly constructed by integrating com- plementary metal-oxide semiconductor (CMOS) field-effect transistor-based active elements and passive elements such as resistors, inductors, and capacitors suitable for the circuit properties. [6-9] Enhancing the characteristics of the active and passive elements is crucial for the designed circuit, as the characteristics of these elements directly influence the circuit properties. [10,11] Resistors—one of the most common passive elements— are widely used for various purposes, including the termination, attenuation, matching, isolation, and stabilization of RFICs. [12-14] Thin-film resistors (TFRs) have a precise resistance with a smaller error margin than polysilicon resistors and diffusion resistors and can be processed at low temperatures for ensuring a precise resistance. [15-18] TFRs are commonly used in back-end-of-line processes owing to their applicability. [19] However, these resistors are unable to maintain their original resistance properties at high frequencies, because of the influences of parasitic capacitance and parasitic inductance components. The impedance changes over the TFR frequency with 500 Ω. The ideal resistor characteristics are observed below nearly 10 MHz, and a decrease in the impedance is observed up to 10 GHz because of the effect of the parasitic capacitance components. However, this is followed by an increase in the impedance We report the analysis of the radiofrequency (RF) characteristics according to the size, area, and shape of TaN thin-film resistor (TFR) layers. As the TFR size increased, its characteristics were degraded with increasing frequency owing to the increased capacitive parasitic components. As the frequency increased from 1 MHz to 10 GHz, the effective resistance decreased by approximately 12.5%, 16.4%, and 37.8% when the resistor widths and lengths were 0.5 × 20, 1 × 40, and 2 × 80 μm, respectively. To optimize the performance of the high- frequency TFR, ensuring RF isolation via sufficient separation from the silicon substrates was crucial. To realize this RF isolation, methods for minimizing the effect of lossy Si substrates by using TFRs with a smaller area or by forming a patterned ground shield should be introduced. Keywords: thin-film resistor, tantalum nitride thin film, RFIC, patterned ground shield, CMOS, resistance DOI: 10.1007/s13391-017-1723-x *Corresponding author: sgpyo@cau.ac.kr ©KIM and Springer