RF Power Performance of Asymmetric-LDD MOS Transistor for RF-CMOS SOC Design

Abstract

This letter presents a new asymmetric-lightly-dopeddrain (LDD) metal oxide semiconductor (MOS) transistor that is fully embedded in a CMOS logic without any process modification. The radio frequency (RF) power performance of both conventional and asymmetric MOS transistor is measured and compared. The output power can be improved by 38% at peak power-added efficiency (PAE). The PAE is also improved by 16% at 10-dBm output power and 2.4 GHz. These significant improvements of RF power performance by this new MOS transistor make the RF-CMOS system-on-chip design a step further.Index Terms-Lightly-doped-drain (LDD), metal oxide semiconductor field effect transistor (MOSFET), metal oxide semiconductor (MOS) transistor, radio frequency (RF) power transistor.

Improved Radio Frequency Power Characteristics of Complementary Metal–Oxide–Semiconductor-Compatible Asymmetric-Lightly-Doped-Drain Metal–Oxide–Semiconductor Transistor

“…To increase the breakdown voltage of an asymmetric-LDD MOSFET, the drain LDD region was removed by an n þ ion-implantation blocking mask. 15) Conventional MOSFETs were also fabricated for comparison. The p-type region undernearth the drain spacer forms a wider depletion region to allow a larger applied drain voltage.…”

“…To address above issues, we proposed a new asymmetric lightly-doped-drain (LDD) MOS transistor. 15) Using the 0.25 mm technology, this device showed high drain breakdown voltage and preserved a high f T and f max for high frequency operation at the same time. The realization of both the high power density and low ACRP is difficult when scaling the gate length (L g ).…”

High performance RF passive devices and noise-shielding MOSFET on IC-standard Si wafer for sub-THz applications

“…Such excellent high frequency performance allows the IC operated at sub-THz regime. However, the fundamental challenges of Si-based millimeter wave IC are the much poorer performances of passive devices [1]- [9], transistor noise figure (NF) [10]- [11], and output power of MOSFET [12] than those on GaAs. The measured power loss of CPW transmission line on Si wafer is as high as 5 dB/mm at 110 GHz, which will increase with increasing frequency toward THz.…”