Plasma enhanced atomic layer deposition was used to deposit thin films of Ga2O3 on to c-plane sapphire substrates using triethylgallium and O2 plasma. The influence of substrate temperature and plasma processing parameters on the resultant crystallinity and optical properties of the Ga2O3 films were investigated. The deposition temperature was found to have a significant effect on the film crystallinity. At temperatures below 200°C amorphous Ga2O3 films were deposited. Between 250°C and 350°C the films became predominantly α-Ga2O3. Above 350°C the deposited films showed a mixture of α-Ga2O3 and ε-Ga2O3 phases. Plasma power and O2 flow rate were observed to have less influence over the resultant phases present in the films. However, both parameters could be tuned to alter the strain of the film. Ultraviolet transmittance measurements on the Ga2O3 films showed that the bandgaps ranges from 5.0 eV to 5.2 eV with the largest bandgap of 5.2 eV occurring for the α-Ga2O3 phase deposited at 250°C.
Single-crystalline high-quality beta-Ga2O3 pseudo-substrate on sapphire through sputtering for epitaxial deposition
University of Wisconsin-Madison（威斯康星大学麦迪逊分校）；Agnitron Technology Incorporated（阿格尼特龙科技有限公司）；University of Massachusetts Lowell（马萨诸塞大学洛厄尔分校）；Center for High Technology Materials, University of New Mexico（新墨西哥大学高等材料研究中心）
Spot Profile Analysis Low Energy Electron Diffraction of Plasma-Enhanced Chemical Vapor Deposition Grown Epitaxial Few-Layer Graphene on Sapphire
University of Duisburg-Essen（杜伊斯堡-埃森大学）；Faculty of Engineering, University of Duisburg-Essen（杜伊斯堡-埃森大学工程学院）；Department of Chemistry and Waterloo Institute for Nanotechnology（化学系与滑铁卢纳米技术研究所）；Center for Nanointegration (CENIDE)（纳米集成中心）
Demonstration of Si-doped Al-rich thin regrown Al(Ga)N films on AlN on sapphire templates with $\gt10^{15}/cm^3$ free carrier concentration using close-coupled showerhead MOCVD reactor
HVPE growth of corundum-structured $α$-Ga$_2$O$_3$ on sapphire substrates with $α$-Cr$_2$O$_3$ buffer layer
采用射频磁控溅射法在（0001）蓝宝石衬底上制备了含和不含$α$ $_2$ O $_3$缓冲层的氧化镓薄膜.在裸蓝宝石衬底上的沉积导致$α$ $_2$ O $_3$和$ε$-Ga $_2$ O $_3$相的混合物，位错密度约为$2\cdot10^{10}$ cm $^{-2}$ . $α$ -Ga $_2$ O $_3$缓冲层的插入导致相位纯的$α$ -Ga $_2$ O $_3$膜和位错密度的四倍减少到$5 \cdot 10^9$ cm $^{-2}$。
Going beyond copper: wafer-scale synthesis of graphene on sapphire
石墨烯在电子学、光电子学和光子学中的采用受到以下阻碍：难以在技术相关的衬底上获得高质量的材料、超过晶片级尺寸并且金属污染水平与工业要求兼容。迄今为止，石墨烯在绝缘衬底上的直接生长已被证明是具有挑战性的，通常需要金属催化剂或产生有缺陷的石墨烯。在这项工作中，我们展示了一种无金属的方法，在市售的反应器中，通过化学气相沉积（CVD）在c平面蓝宝石衬底上获得高质量的单层石墨烯。我们通过低能电子衍射（LEED）、低能电子显微镜（LEEM）和扫描隧道显微镜（STM）测量确定蓝宝石的富Al重构根31 R9对于获得外延石墨烯是至关重要的。拉曼光谱和电输运测量揭示了高质量的石墨烯，其迁移率始终高于2000 cm 2/Vs。我们将该工艺扩展到4英寸和6英寸的晶圆尺寸，并证明金属污染水平在后端线（BEOL）集成的限制范围内。这里介绍的生长过程建立了一种在技术上可行的基础上合成晶片级石墨烯膜的方法。
