RF characteristics of 0.13-μm NMOS transistors for millimeter-wave application

Abstract

Purpose

The purpose of this paper is to present the high-frequency performance of 0.13-μm n-type metal-oxide-semiconductor (NMOS) transistors with various multi-finger configurations for implementation in millimeter-wave (mm-wave) frequency.

Design/methodology/approach

A folded-like double-gate transistor layout is designed to enable the transistor to work in the mm-wave region. Different sizes of transistors with variation in finger width (W_F ) and number of fingers (N_F ) were fabricated to determine the optimum size of the transistor. The extrinsic parasitic elements of selected transistors were extracted and investigated. The radio frequency (RF) performance of these samples were then analyzed and compared.

Findings

The proposed layout performed well with the highest maximum oscillation frequency (f_max ) achieved at 122 GHz. Based on the comparison done, the optimum W_F obtained for the layout is at 2.0 μm. It is found that the extrinsic parasitic capacitance is more dominant than the parasitic resistance in affecting the f_max . In s-parameter analysis, it is observed that the transistor with the least N_F has smaller variance in small-signal gain throughout the measurement frequency. The maximum stable gain for the samples is also found to be roughly similar and independent of N_F .

Originality/value

A new layout structure for an NMOS transistor that works in mm-wave frequency is proposed. Experimental analyses presented here cover for both N_F and W_F , unlike others which focus on either N_F or W_F only.

Citation

Maisurah Mohd Hassan, S., M. Yusof, Y., Marzuki, A., Emran Farid, N., Amalina Enche Ab Rahim, S. and Hafis M. Ali, M. (2014), "RF characteristics of 0.13-μm NMOS transistors for millimeter-wave application", Microelectronics International, Vol. 31 No. 2, pp. 116-120. https://doi.org/10.1108/MI-09-2013-0044