Changes in semiconductor materials

Ge (germanium), Si (silicon) → GaAs (gallium arsenide), InP (indium phosphide) → SiC (silicon carbide), GaN (gallium nitride), SiGe (silicon germanium),SOI ( The insulating layer is coated with silicon) → carbon nanotube (CNT) → graphene (Graphene).

At present, the mainstream technology of rf power amplifier is still GaAs technology. In addition, GaAs HBT, gallium arsenide heterojunction bipolar transistor. Which our HBT (heterojunction bipolar transistor) is composed of gallium arsenide (GaAs) and aluminum gallium arsenic (AlGaAs) layers of abipolar transistor.

The current mainstream technology of rf amplifier is still GaAs technology. Although the CMOS process is relatively mature, Si CMOS rf amplifiers are not widely used. In terms of cost, although the CMOS process silicon wafers are cheaper, the CMOS power amplifier layout area isrelatively large, coupled with the high R & D cost of the complicated design of CMOS PA, the overall cost advantage of the CMOS microwave amplifier is notso obvious. In terms of performance, CMOS power amplifiers have poor performance in terms of linearity, output power, efficiency, etc., plus the inherentdisadvantages of CMOS technology: higher knee voltage, lower breakdown voltage, and resistance of CMOS process substrate substrate The rate islower.

Carbon nanotubes (CNTs) are considered to be ideal materials for nanoelectronic devices due to their small physical size, high electron mobility, largecurrent density, and low intrinsic capacitance.

Zero-gap semiconductor material graphene, because of its high electron migration rate, physical size on ththe order of nanometers, excellent electricalproperties and mechanical properties, will surely become a popular material for next-generation RF chips.