Investigation of halide vapor phase epitaxy of In2O3 on sapphire (0 0 0 1) substrates

Growth of twin-free cubic In2O3(111) thick layers on c-plane sapphire substrates by halide vapor phase epitaxy

“…The previously described atmospheric-pressure hot-wall HVPE system 24) was used for heteroepitaxial growth of the c-In 2 O 3 (111) layers. c-plane sapphire substrates with off-axis angles (D a ) of 0°-10°in the [1120] direction were used.…”

“…More details concerning the growth procedure are provided in our previous report. 24) The surface morphology and thickness of the grown layers were evaluated by surface and cross-sectional observations using field-emission scanning electron microscopy (FE-SEM; JEOL, JSM-6700F). Using high-resolution X-ray diffraction (XRD; Spectris, X'Pert MRD), the out-of-plane and in-plane crystal orientations were evaluated by 2θ-ω scan and polefigure measurements, respectively, and crystallinity was examined by X-ray rocking curve (XRC) measurements.…”

“…[10][11][12][13] However, it is essential to prepare high-quality In 2 O 3 single-crystal layers with a low carrier density and a high carrier mobility to realize such novel devices. In recent years, the growth of single-crystal layers of cubic In 2 O 3 (c-In 2 O 3 ), which is a thermally stable phase with the bixbyite structure, has been attempted using various growth methods, such as pulsed laser deposition, [14][15][16] molecular beam epitaxy (MBE), [17][18][19] metalorganic chemical vapor deposition (MOCVD), 20,21) halide vapor phase epitaxy (HVPE), [22][23][24] and low-pressure CVD (LPCVD). 25,26) The lowest electron density and the highest electron mobility at room temperature (RT) reported to date are 6 × 10 16 cm −3 and 226 cm 2 V −1 s −1 , respectively, which were achieved with an unintentionally doped c-In 2 O 3 layer grown by MBE.…”

“…22) In the growth of c-In 2 O 3 layers on cplane sapphire substrates, mixed growth of (100)-and (111)oriented domains is likely to occur; however, it was most recently reported that growth of the (111)-oriented domains becomes dominant when the growth temperature is raised to 1000 °C. 24) HVPE growth of high-purity (111)-oriented c-In 2 O 3 layers is now possible on c-plane sapphire substrates. However, there are still twinned domains rotated in-plane by 180°with respect to each other, so that the electron mobility at RT is limited to about 134 cm 2 V −1 s −1 , even though the electron density is as low as 6 × 10 16 cm −3 .…”

Высокая Чувствительность Пленок Оксида Индия, Полученных Методом Хлоридной Газофазной Эпитаксии, К Аммиаку

“…Оксид индия -металлооксидный полупроводник n-типа проводимости, который за счет оптической прозрачности в видимой области спектра (ширина запрещенной зоны E g = 3.5−3.7 эВ [1][2][3][4][5]), низкой эффективной массы электронов (m n = 0.16−0.25 m [3,6,7]), высокой каталитической активности и проводимости, вызванной наличием дважды ионизированных вакансий кислорода, получил широкое распространение и может быть использован в газовых сенсорах, солнечных элементах, сенсорных и жидкокристаллических дисплеях, тонкопленочных транзисторах, оптоэлектронных и фотоэлектрических устройствах, контактах и диодах Шоттки [1][2][3][4][5][8][9][10][11][12][13][14][15][16][17][18]. Столь обширные и разнообразные области применения чаще относят к In 2 O 3 : Sn [1,3,5,8], в то время как свойства нелегированного In 2 O 3 наиболее активно исследуют для газовой сенсорики [1,2,[11][12][13][14][15][16][17][18]. In 2 O 3 обладает полиморфизмом и в качестве основных полиморфных модификаций выделяют три: объемоцентрированный кубический c-In 2 O 3 ; ромбоэдрический rh-In 2 O 3 и орторомбический o-In 2 O 3 .…”