Study On The Characteristics And Photoelectric Properties Of Gold-oxygen Terminated Type ?a Diamond Interface

Due to the bottleneck of shallow-level doping technology,the diamond device prepared by doping technology still fails to exert the performance level determined by the characteristics of diamond material.The diamond-rich surface terminal has become an optional technical solution for diamond device technology.The hydrogen terminal acts as a conductive channel for the FET and exhibits excellent high frequency characteristics.However,the hydrogen terminal is not suitable for interface contact technology of MIP power diode.The barrier height formed by the contact between hydrogen terminal diamond and Al,Ti,Ni,Au and Pd is less than 0.6e V,which can easily lead to the disadvantage of devices such as large reverse current,small rectification ratio and strong breakdown field.In addition,the thermal stability of hydrogen terminal devices is poor.The barrier height formed by the contact between oxygen terminal diamond and metal is 2 to 3 times higher than that of the hydrogen terminal,which is more able to withstand the reverse high voltage than hydrogen terminal,and oxygen terminal can work stably at a high temperature of 400 ° C.Therefore,metal and oxygen termination Schottky junction technology is the mainstream technology of MIP power diodes.At present,the study of oxygen terminal contact characteristics is based on the contact of boron-doped diamond and metal,but the contact characteristics between oxygen terminal IIa diamond and metal are rarely studied.However,the Schottky junctions of MIP power diodes and photoconductive solar-blind ultraviolet detectors are formed by the contact between metal and type IIa diamond,so it is necessary to study the contact characteristics between metal and type IIa diamond.Aiming at the theoretical data requirement of MIP power diode,photoconductive solar-blind ultraviolet detector and other diamond-based Schottky junction application technologies for the contact characteristics of metal-oxygen terminal IIa diamond,the surface and interface characteristics of oxygen terminal IIa diamond were studied in this dissertation.At the same time,based on the contact technology of gold-oxygen terminal type IIa diamond,the charge state conversion of the NV color center is realized;the regulation of the Schottky barrier by ultraviolet light is found,and the Schottky junction position sensitive detector is developed;The traditional back-to-back Schottky junction solar blind UV detector structure is optimized.By means of X-ray photoelectron spectroscopy,ultraviolet photoelectron spectroscopy and Kelvin probe force,it is confirmed that oxygen atoms exist on the surface of diamond in the form of C=O suspension and(1×1)reconstruction;The affinity energy of oxygen terminal type IIa diamond and the height of Schottky barrier and the difference of work function of diamond-oxygen terminal type IIa diamond are mastered;The surface state band model of oxygen terminal is proposed,and the contradiction between theoretical and experimental data is solved;Considering that nitrogen element is the main impurity in type IIa diamond,the relationship between the width of depletion layer and nitrogen concentration of type IIa diamond Schottky junction is deduced.The charge state of NV color center is regulated by the gold-oxygen terminal diamond Schottky junction.The experimental phenomenon that NV-fluorescence is suppressed while NV0 is not affected by Schottky junction is found;The mechanism of regulation is studied,and the NV-non-fluorescent state model is proposed,which overturns the traditional understanding of the charge state transition of NV color center;In addition,the relationship between the thickness of suppressing layer and nitrogen concentration was deduced.Four-quadrant gold-oxygen terminal diamond Schottky electrode structure was fabricated.The experimental phenomena of dark current symmetry and photocurrent asymmetry were found.The influence of spot position on photocurrent was studied.The mechanism of light regulating barrier height in the Schottky junction of diamond-oxygen terminal was explored,and the performance of ultraviolet position sensitive detection was explored.Considering the influence of the penetration depth and electric field distribution of ultraviolet light in diamond on carrier collection efficiency,I)On the basis of back-toback Schottky detection structure,Schottky back electrode was added to improve the detection performance of traditional structure diamond solar blind ultraviolet detector;II)The 3-D structure of diamond back-to-back Schottky electrode was designed and developed by ICP etching and metal iron etching,respectively..In this dissertation,the research on the surface and interface characteristics of oxygen terminal IIa diamond is helpful to clarify its physical image and improve its theory,and to guide the design and performance analysis of diamond-oxygen terminal Schottky junction devices.As an example in the field of contact between metal and semiconductor,some research results are also generally applicable to other metal-semiconductor systems,which is a supplement to the traditional classical semiconductor theory.In addition,the photoelectric application of diamond-oxygen terminated Schottky junction is studied in this paper,which expands the application field of diamond-oxygen terminated Schottky junction and understands some photoelectric characteristics of diamond-oxygen terminated Schottky junction.