Research Of GaN Thin Film Deposited On ZrB₂/Ni Substrate Under Low-temperature

Metal nickel?Ni?is a hard and flexible silver white metal.The number of atomic number is 28.It has good thermal conductivity and conductivity,high reflectivity,low manufacturing cost and easy to make large area material.Because the lattice constant of its a axis is0.35288nm and the lattice constant of GaN is close to each other,it becomes one of the choices to prepare substrates for GaN thin film functional materials.Two Zirconiumboride?ZrB₂?is a semi metal compound,which belongs to the six-party crystal system and has many properties,such as high melting point,high strength,high hardness,good conductivity and thermal conductivity,and good corrosion resistance.The lattice constant of the a axis of ZrB₂ is very close to that of the GaN lattice constant 0.3189nm,which will reduce the lattice mismatch in the preparation and use,and improve the properties of the materials.Therefore,Zr B₂ is considered to be an excellent material for buffer layer of GaN thin films.Gallium nitride?GaN?is a direct broadband gap semiconductor nitride,which has the characteristics of low production cost and excellent photoelectric characteristics.GaN materials can be used not only in the field of high frequency and large power devices,but also because the band gap of GaN can cover the range of the entire visible spectrum,so it has an important position in the field of short wave long optical electronic devices.In recent years,with the maturity of GaN material manufacturing technology,GaN based blue light emitting diode?LED?has been developing rapidly.In this paper,the magnetron sputtering system?JGP-450?was used,and the metal Ni treated by mechanical polishing was used as the substrate,and the RF magnetron sputtering was used to sputter the ZrB₂ film materials.The process parameters of suitable film growth are discussed by means of various thin film characterization methods.The electron cyclotron resonance plasma enhanced metal organic chemical vapor deposition?ECR-PEMOCVD?device was used to deposit the GaN thin film at low temperature using the obtained Zr B₂/Ni.After a series of tests and analysis,the effects of different three methyl gallium?TMGa?flow rate on the deposition quality and photoelectric properties of GaN thin films were discussed.By testing and analyzing,we can know that the interface of GaN/ZrB₂ heterojunction has electron tunneling,which shows ohmic contact characteristics.