With the development of astronautic techniques, the radiation effects on Integrated Circuits (ICs) have been cognized by people. Environments with high levels of ionizing radiation create special design challenges for ICs. To ensure the proper operation of such systems, manufacturers of integrated circuits and sensors intended for the military aerospace markets adopt various methods of radiation hardening. An overview of radiation hardening techniques for IC design is given in this study. First, seven major radiation damage sources, two fundamental damage mechanisms, five sorts of end-user effects and six types of single-event effects are introduced, followed by the brief introduction of radiation hardening techniques. Secondly, typical physical radiation hardening techniques are introduced. Thirdly, typical logical radiation hardening techniques are introduced. Fourthly, we propose our radiation hardening scheme for microwave power amplifier chip design. Here, a Radio-Frequency (RF) Power Amplifier (PA) is a sort of electronic amplifier employed to convert a low-power radio-frequency signal into a larger signal of significant power, typically for driving the antenna of a transmitter. Finally, we concluded the whole study.