Sapphire and gallium oxide have been used as substrates for most of the reported results on β-Ga₂O₃ devices. However, silicon (Si) is an abundant material on the Earth, leading to easier and low-cost availability of this substrate, along with higher thermal conductivity, which makes Si a promising and potential substrate candidate for rapid commercialization. Therefore, in order to strengthen the feasibility of Ga₂O₃ on Si integration technology, we have deposited β-Ga2O3 on (100) and (111) oriented p-Si substrates using a pulsed laser deposition technique. A single-phase (β) and polycrystalline nature of the β-Ga₂O₃ film is observed for both samples using x-ray diffraction. A low root mean square roughness of 3.62 nm has been measured for Ga₂O₃/Si(100), as compared to 5.43 nm of Ga₂O₃/Si(111) using atomic force microscope. Moreover, Ga₂O₃/Si(100) shows a smoother and uniform surface of the Ga₂O₃ film, whereas Ga₂O₃/Si(111) seems to have a rougher surface with pitlike defects. This might be due to the hexagonal projection of Si (111) that is not suitable for obtaining a good tilted cuboid or monoclinic Ga₂O₃ crystal unlike the rectangle projection of Si (100). The electrical parameters of the fabricated Schottky barrier diodes were extracted using current–voltage (I–V) and capacitance–voltage (C–V) characteristics. The polycrystalline Ga₂O₃ film on Si(100) leads to fewer defects emerging from the Ga₂O₃/Si heterointerface due to the close symmetry of Ga₂O₃ and the Si(100) crystal with rectangle projections unlike Ga₂O₃ on Si(111). These fewer defects eventually lead to a better diode performance of Ga₂O₃/Si(100) where we have observed typical thermionic dominating carrier transport, whereas defect-assisted thermionic field emission has been the primary carrier transport mechanism in Ga₂O₃/Si(111). Hence, the Si (100) substrate is demonstrated to be a better and potential platform for Ga₂O₃ devices than Si (111).

中文翻译：

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β-Ga2O3/ Si基肖特基势垒二极管中与衬底方向相关的电流传输机制

蓝宝石和氧化镓已被用作底物对于大多数报告结果的上的β-Ga ₂ ö ₃设备。但是，硅（Si）是地球上一种丰富的材料，导致该衬底更容易且成本更低，并且热导率更高，这使Si成为快速商业化的有希望和潜在的衬底候选者。因此，为了增强Ga ₂ O ₃在Si集成技术上的可行性，我们使用脉冲激光沉积技术在（100）和（111）取向的p-Si衬底上沉积了β-Ga2O3。单相（β）和所述多晶性质的β-Ga ₂ ö ₃使用X射线衍射观察两个样品的薄膜。使用原子力显微镜测得的Ga ₂ O ₃ / Si（100）的均方根粗糙度低至3.62 nm ，而Ga ₂ O ₃ / Si（111）的均方根粗糙度为5.43 nm 。而且，Ga ₂ O ₃ / Si（100）显示出Ga ₂ O ₃膜的光滑且均匀的表面，而Ga ₂ O ₃ / Si（111）似乎具有带有坑状缺陷的粗糙表面。这可能是由于Si（111）的六边形投影不适合获得良好的倾斜长方体或单斜Ga ₂ O ₃晶体不同于Si（100）的矩形投影。的电参数使用制作电流-电压（肖特基势垒二极管中提取余- V）和电容-电压（C ^ - V）特性。多晶镓₂ ö ₃上的Si膜（100）导致较少的缺陷从Ga的新兴₂ ö ₃ / Si的异质由于Ga构成的接近对称₂ ö ₃和与不同于嘎矩形突起生长的Si（100）晶₂ ö Si（111）上为₃。这些较少的缺陷最终导致Ga ₂ O的二极管性能更好₃ / Si（100）中，我们观察到典型的热电子占主导地位的载流子传输，而缺陷辅助热电子场发射一直是Ga ₂ O ₃ / Si（111）中的主要载流子传输机制。因此，与Si（111）相比，Si（100）衬底被证明是用于Ga ₂ O ₃器件的更好且潜在的平台。