Radio frequency integrated circuit chip and its forming method

Abstract

A radio frequency integrated circuit chip and a method for forming the same, the radio frequency integrated circuit chip comprising: a semiconductor substrate having a shallow trench isolation structure in the semiconductor substrate; a filling layer penetrating through the shallow trench isolation structure and filling the Part of the semiconductor substrate is used to separate the semiconductor substrate from the shallow trench isolation structure; a dielectric layer is located on the semiconductor substrate, the shallow trench isolation structure and the filling layer; a radio frequency device , located on the dielectric layer. Since the semiconductor substrate and the shallow trench isolation structure are separated by a filling layer, it is possible to prevent the formation of a charge inversion layer or a charge accumulation layer between the semiconductor substrate and the shallow trench isolation structure, thereby preventing the semiconductor substrate from appearing similar to The conductive layer of the channel, so there will be no coupling capacitance between the radio frequency device and the semiconductor substrate, and when the radio frequency signal passes through the device, no harmonic distortion will occur, which improves the transmission quality of the radio frequency signal.

Description

technical field [0001] The invention relates to the field of semiconductor manufacturing, in particular to a radio frequency integrated circuit chip and a forming method thereof. Background technique [0002] Radio Frequency Integrated Circuit (RFIC), strictly speaking, refers to analog circuits that work in the frequency band above 0.8GHz, including microwave and millimeter wave circuits. [0003] Radio frequency integrated circuits mainly include filters, low noise amplifiers (LNA), voltage controlled oscillators (VCO), mixers, amplifiers / drivers, frequency synthesizers, power amplifiers (PA) and power management circuits. These radio frequency integrated circuits can be used to form a radio frequency transceiver, in which LNA, VCO, mixer, driver, etc. can be used to form the receiving front end of the signal receiving chain, that is, the receiver system; and the frequency synthesizer and power amplifier are used to form the transmitter. . The application of radio freque...

AI Technical Summary

Problems solved by technology

[0004] For the radio frequency integrated circuit chip (Chip) on the semiconductor substrate, when the radio frequency signal passes through active devices and passive devices (such as transmission lines or inductors) in the radio frequency integrated circuit, the radio frequency signal will be coupled with the semiconductor substrate , leading to harmonic distortion (Harmonic Distortion), which will have a great adverse effect on the linearity of the signal

[0005] To this end, a new radio frequency integrated circuit chip and its formation method are needed to prevent harmonic distortion caused by coupling between radio frequency signals and silicon-on-insulator substrates

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