Fabrication And Gate Optimization Of Photosensitive Gate GaN-based HEMT Devices

The research on infrared devices of ferroelectric materials is very active.Because ferroelectric materials have good characteristics of piezoelectric,ferroelectric,pyroelectric,optoelectronic and nonlinear optics,and can be integrated with semiconductor processes,in microelectronics and optoelectronics.The field has broad application prospects and has become a novel functional material,which has received extensive attention and attention.Among them,lead zirconate titanate(PZT)ferroelectric thin film is the most widely studied and widely used type of ferroelectric thin film.Materials,PZT films have high electromechanical coefficient,high dielectric constant and high remanent polarization.They are widely used in the fabrication of MEMS and nanodevices,such as infrared detectors,memories,sensors and ultrasonic devices.The combination of thin films and semiconductor devices has become the mainstream in the field of microelectronics.The anomalous photovoltaic effect of PZT film can produce stable photoinduced current and photogenerated voltage much larger than the crystal forbidden band width(Eg)under certain wavelength illumination,especially the photovoltaic response can be regulated by external electric field.It has broad application prospects in infrared photovoltaic detectors.In particular,in combination with a GaN-based HEMT(High Electron Mobility Transistor)device,the photon and pyroelectric characteristics of the PZT thin film convert the absorbed photons into electrons,thereby changing the gate voltage of the HEMT device,causing the input current to change achieve the radiated light.The role of detection.The infrared detector prepared by combining the different properties of ferroelectric materials with GaN-based HEMT devices has a wide infrared range,which can be detected from visible light to far infrared,and since the AlGaN/GaN heterojunction utilizes spontaneous polarity The high-density two-dimensional electron gas(2DEG)formed by the polarization and piezoelectric polarization effects has a mobility of up to 2000 cm~2/(V·s).Based on this feature,the detection is performed using an AlGaN/GaN HEMT device.The device is not only sensitive,but also has a fast response rate,and has a wide detection area to adapt to harsh environments.However,there are still many problems affecting device performance in the research of GaN-based HEMT devices themselves.In this paper,a ferroelectric thin film PZT is combined with an AlGaN/GaN HEMT device,and a conductive metal electrode is deposited on the gate of the HEMT device,and a sensitive unit PZT having a photovoltaic effect is deposited thereon,wherein the PZT film utilizes magnetic control Prepared by sputtering method,the sputtering power is 100W,200W,and the post-annealing temperatures are 650?,700?and 750?respectively.Different sputtering powers and different annealing are performed by X-ray diffractometer(XRD)and scanning electron microscope(SEM).The morphology and composition of the temperature PZT film were characterized.The HEMT device of the light-sensitive gate is tested,and the IV characteristic is tested by using 365 nm visible light.The parameters of the gate length and the distance between the gate and the drain of the HEMT device are changed to analyze the IV curve and the transfer curve after illumination.Changes to achieve the goal of optimizing the performance of light-sensitive gate HEMT devices.