本實驗研究中主要可分為三部分：探討鈦金與β-Ga2O3之歐姆接觸狀況並利用TEM和EDS分析介面關係；蕭特基方面透過利用溼式蝕刻、乾式蝕刻、熱退火處理來得到良好特性的Pt/β-Ga2O3蕭特基二極體，利用熱離子發射理論來推導其電性參數，例如低導通電阻、高能障和高整流比來證實本實驗製程方法可以得到好的Pt/β-Ga2O3蕭特基二極體，並更進一步利用變溫測量來取得變溫參數，得到蕭特基能障、內建電位和導通電阻的變溫曲線。本實驗最好的結果為蕭特基能障1.355eV、理想因子為1.02、飽和電流密度為5.88x10-17A/cm2，其中Richardson常數為 44.82A/cm2K2，非常接近理論值 41.11 A/cm2K2；缺陷偵測利用暫態電容和導納頻譜量測，找出缺陷位置在傳導帶以下 0.81eV 和0.1eV，其缺陷濃度分別為1.2x1016cm-3、4.2x1016cm-3、捕捉截面積分別為 1.1x10-14cm2、1.7x10-18cm2。

The results of this experiment can be divided into four major projects: the first one is to investigate the ohmic contact results of titanium metal and β-Ga2O3. After the wet etching of the β-Ga2O3 substrate, the thermal annealing treatment of 400oC, 450oC, 470oC and 500oC is respectively performed. The difference in non-rectifying electrical properties is discussed, and the best ohmic thermal annealing condition is 450oC for one minute. Under the area width of 200μm and 1500μm, the total resistance is about 6 Ω, and the contact resistance is 0.78 Ω by the traditional TLM method. In addition, the thermal annealing parameter 500 oC was the worst condition, and the surface condition after thermal annealing 450 oC and thermal annealing 500oC was examined by TEM electron microscope and EDS elemental analysis. It can be found in TEM image and EDS analysis that the degree of interface element diffusion after thermal annealing 450oC does not cause too much substrate damage. The second research project is Pt /β-Ga2O3 Schottky diode. We have made Pt /β-Ga2O3 Schottky diode with good performance characteristics by wet etching, dry etching and thermal annealing. During the etching phase, it is found that under the condition of only organic cleaning, an abnormal rectification characteristic curve appears, like two Schottky diodes, one Schottky diode which is affected by defects and reduces energy barrier, and another One is a normal Schottky diode. After the hydrochloric acid etching for 5 minutes, the double Schottky diode effect can be effectively improved, but as a result, the electrical leakage current is still quite large. Finally, on the wet etching, the substrate is immersed in 85oC boiling hydrogen peroxide for five minutes to obtain a low leakage current Pt /β-Ga2O3 Schottky diode. The leakage current effect is less than the photocurrent effect, so it will appear electrically. Zero offset phenomenon, which proves Pt /β-Ga2O3 Schottky diode with low leakage current on wet etching. In dry etching, the best parameters are found to effectively reduce the on-resistance and series resistance of the Pt /β-Ga2O3 Schottky diode. The best parameters for dry etching are ICP-RIE (400w/30w) and the gas flow rate is BCl3/Ar (35sccm/5sccm), operating environment pressure is 1.33mPa, but the side effect of dry etching is to increase the saturation current density of Pt /β-Ga2O3 Schottky diode, so the next step is to effectively reduce the saturation current density of Pt /β-Ga2O3 Schottky diode by thermal annealing. Finally, using the thermal annealing process, it can be found that after the continuation of the above process, the thermal annealing 450oC can effectively reduce the saturation current density of the Pt /β-Ga2O3 Schottky diode, and slightly reduce the resistance value of the Pt /β-Ga2O3 Schottky diode. In addition, under the condition of thermal annealing of 500oC, the Pt /β-Ga2O3 Schottky diode has the lowest resistance value, but its saturation current density has not decreased effectively. Therefore, the built-in potentials of the two were analyzed by capacitance voltage measurement, and the surface condition after thermal annealing 450oC and thermal annealing 500oC was examined using TEM electron microscopy and EDS elemental analysis. Further analysis of the TEM image, using Fourier transform to obtain the equivalent of the lattice scattering image, and then using the inverse Fourier transform to find that the lattice spacing is changed, and we use thermionic emission theory to obtain the electrical parameters we prepared, Such as low on-resistance, high energy barrier and high rectification ratio, it is confirmed that the experimental process can obtain a good Pt /β-Ga2O3 Schottky diode.
The third research project is the performance of electrical properties under variable temperature, using temperature-varying measurements to obtain parameters of temperature changes, Schottky barriers, built-in potentials and on-resistance temperature curves. The best result is Schottky energy barrier 1.355eV, saturation current density 5.88x10-17A/cm2, ideal factor 1.02, Richardson constant 44.82 A/cm2K2,, very close to the theoretical value of 41.11 A/cm2K2, and successfully obtained from 7.5K to 700K The electrical characteristics of the performance are the first to study the electrical properties of Pt /β-Ga2O3 Schottky diodes under a wide range of temperature changes. The last research project is to discuss defects, and defect detection can be divided into two ways. The first detection defect is the use of transient capacitance and temperature measurement in the range of 17oC to 57oC. The second detection defect is the use of admittance spectroscopy and temperature measurement in the range of 185K to 245K, and the Arrhenius plot can be found by the above two methods for finding defects, which can respectively find the defect location 0.81eV and 0.1eV below the conduction band. The defect concentrations are 1.2x1016cm-3 and 4.2x1016cm-3, respectively. The capture cross-sectional areas are 1.1x10-14cm2 and 1.7x10-18cm2, respectively. The results of the defect experimental data have been published in the Japanese Journal of Applied Physics under the title β-Ga2O3 defect study by steady-state capacitance spectroscopy.

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