Analysis of Harmonic Distortion in UDG-MOSFETs

In this paper, the harmonic distortion (HD) in the underlap double-gate MOSFETs (UDG-MOSFETs) with high- k spacers is analyzed. The HD occurs due to the nonlinearity in the device performance and therefore, a detailed analysis of the HD as a function of spacer dielectric constant (k) is critical to ensure device reliability for RF performance. In this paper, the analysis is performed for the primary components, the second-order distortion (HD2), and the third-order distortion (HD3) along with the total HD. The parameters analyzed for the HD study of the UDG-MOSFETs with high- k spacers are the drain current, the transconductance, and the transconductance generation factor. The results of the analysis suggest a reduction in the distortion phenomenon for the high- k spacer devices, thereby ensuring reliability of these devices for RF applications. Also, a detailed analysis of HD2 and HD3 as a function of k of the high- k spacers are performed using UDG-MOSFETs in cascode and differential amplifier circuits.