Analysis of Performance-Influencing Factors and Optimization Strategies for Single-Stage Amplifiers

When semiconductor technology scales down steadily, single-stage amplifiers have significant difficulties in optimizing performance because of short-channel effects and parasitic parameters. This paper thoroughly looks into the important physical mechanisms constraining amplifier gain, with a focus on channel length modulation (CLM), the body effect, and the Miller effect. The study first finds out the theoretical effect of these factors on voltage gain, linearity, and bandwidth. To overcome these limitations, advanced device architectures like Gate-All-Around (GAA) and Fully Depleted SiliconOn-Insulator (FD-SOI) are studied, using their better electrostatic control to suppress CLM and the body effect. Precisely, a Cascode structure making use of active feedback (transistor T2) is proposed to remove the Miller effect. The research reveals that the combination of advanced process nodes and optimized circuit topologies is crucial for getting high gain and high bandwidth performance in modern analog integrated circuits.