Preparation Of Graphene/GaAs-based HEMT Heterojunction THz Detector

According to the frequency to high to low,the electromagnetic wave is divided into X-ray,ultraviolet,visible light,infrared,microwave,long-wave radio and so on.The widespread application of sulphur has aroused great research interest.Most of the reported equipment requires a low temperature working environment.Conventional semiconductor photodetectors rely on the light excitation of electron-hole pairs in semiconductors,which is not suitable for the detection of sub-millimeter/THz photons.The most commonly used sub-millimeter/terahertz detectors include Golay batteries,thermionic bolometers,and pyroelectric detectors.Due to the thermal sensing mechanism,this type of detector responds very slowly because the modulation frequency of Golay batteries and thermoelectric detectors is only a few hundred hertz,or it must be cool about liquid helium.In contrast,Schottky barrier diodes?SBDs?,which exhibit high-speed response at room temperature,require the use of sophisticated techniques in device manufacturing and material production.As a result,their chip integration is currently hindered.Therefore,there is an urgent need for a new detection scheme capable of providing fast response,RT operation,high sensitivity,And easy to make.In the past few years,great efforts have been made for development of field effect transistor-based millimeter wave and terahertz photodetectors.In recent years,graphene and other two-dimensional materials have been shown to detect long-wavelength photons.In recent years,graphene detectors including field-effect transistors,thermionic side-measurement bolometers 13 and optoelectronic electronic devices 11 have made great progress.Detectors based on graphene field-effect transistors perform well in RT and 300 GHz bands.Gallium arsenide?GaAs?is a III-V semiconductor material with a similar sphalerite structure similar to diamond.It is a direct bandgap semiconductor with a band gap of 1.42 eV.The mobility of electrons in gallium arsenide is very high,about 6 times that of silicon,and its saturated electron drift rate is extremely high.GaAs/graphene-based sub-millimeter/THz photodetectors have not been reported.Therefore,in this work,we designed and manufactured graphene/GaAs heterostructure-based photodetectors.Optical response results report errors in the sub-millimeter range and terahertz range to verify the availability of higher THz response using vdW heterostructures.In this work,a millimeter wave photodetector was fabricated using a graphene/gallium arsenide high mobility hetero-transistor structure,which effectively improved the two-dimensional electron gas characteristics and greatly improved the millimeter wave response and detection of the device at room temperature.ability.Experiments show that the device achieves a response rate of 10.2A/W in the 25GHz band with a bias voltage of 400 mV,a response time of 9.8?s,and a detection rate of 1.1×10¹00 cm?Hz^1/2W^-1.In the terahertz wave0.12THz,the response rate still reached 0.4A/W,the response time was 10?s,and the detection rate was 8.15×10¹00 cm?Hz^1/2W^-1.Through the preparation of graphene/gallium arsenide heterostructure photodetectors and corresponding experimental discussion and analysis,the photoresponse and rich response mechanism of the graphene/gallium arsenide heterostructure in the microwave and terahertz bands were verified.The preparation of this work demonstrated the great application prospects of the graphene/gallium arsenide heterostructure millimeter wave terahertz detector.And we further study the response of HEMT devices based on gallium arsenide in the terahertz band.Scanning the optical response between 0.2 THz and 0.3 THz,we can see that the response reaches about 4 nA,the current response rate reaches 12 mA/W,the response time is about 1.5?s,and the response speed is fast.And it can perform stable imaging in the terahertz band.