Study On The Properties Of IGZO And Improvement

It has become one of the core issues in researching TOS materials in the end of20 th century.Indium-Gallium-Zinc(IGZO)oxide thin films as the active layer of amor phous.Indium-Gallium-Zinc TFT(a-IGZO-TFT)has been extensitively researched.It ha s many advantages compared with conventional amorphous Si TFT,high transmission i n visible light,high stability,high electron mobility(>10cm2V-1s-1),low deposition temperat ure,for example.It has wide prospects for application in the fields of Transparent electr onics and flexible electronics,IGZO material is expected to guide the development of d isplay technology in the future.The sol-gel method has a series of advantages,such as l ow cost,simple equipment,which can meet the need of mass production.In this article,the IGZO films were fabricated by solution method and high-pressure annealing process.The effects of H2O2 on microstructural and optical properties of the a-IGZO films were studied by spectroscopic ellipsometry and atomic force microscope(AFM).The main results are as follows:(1)The results indicated that when the annealing temperature was increased from 220? to 300?based on Cauchy model and B-EMA model by spectroscopic ellipsometry.The thickness of surface was decreased from 20.69 nm to 5.02 nm.The microstructural of film observed by AFM showed the same trends.In addition,the refractive index of film was increased from1.64 to 1.91 at the wavelength of 500 nm.The increasing of the optical band cap indicated that the defects in the film was decreased.The dense was closely related to temperature.(2)The IGZO films were fabricated by solution method and high-pressure annealing process,and the effects of H2O2 on microstructural were investigated.Experiment results showed that the refractive of the film with H2O2 was increased and the roughness was decreased obviously under the same high-pressure annealing process,compared to the film without H2O2.Besides the film became smooth observed by AFM.All results indicated that employing H2O2 in the solution could effectively minimize organic chemical residues and pores at lower temperatures,as well as form more dense a-IGZO film.(3)The effects of different content of H2O2 on the properties of the IGZO films were studied.When the content of H2O2 was increased from 0.1ml to 0.25 ml,the thickness of surface was decreased from 4.63 nm to 2.89 nm.As the content of H2O2 continued to increased,the thickness was increased.It was that too much OH reacted with M-O again,the resuilant of reaction leaded to the increasing of defects.The change of the optical band cap confirmed the trends.(4)In order to research the effection structure model on parameter,the three-layer structure model was created.Compared to the four-layer structure model,the refractive index of film was degenerated.The results showed the thickness of surface played an important role in influencing the performances of film.(5)The effects of high pressure on the properties of the IGZO film were studied.Results indicated that the pressure was increased from 0MPa to 2MPa,the thickness of surface was decreased from 32.74 nm to 19.72 nm.