Developments of newer oxysulfide semiconductors for magnetic and fluorescence materials

(1) delafosite型三元氧化物CuAlO_2作为热电应用材料和透明半导体材料受到广泛关注。CuLaO_2是一种延迟岩，因此有望具有宝贵的性质。研究了用固相反应法制备具有辉绿岩型结构的单相cuao_2。结果表明：用La(OH)_3制备的非化学计量组成比为La(OH)_3: Cu_20 =1: 1.425的混合粉末在真空中烧制得到了接近单相的cuao_2，其中含有微量的金属铜。所得CuLaO_2为p型半导体，塞贝克系数为70 μV/K。以La_20_3为原料，在氩气中按化学计量比例烧制得到单相CuLaO_2。掺入Sr或Ca的样品的发射强度比未掺入cuao_2的样品高一个数量级。[2]层状氧化硫化物LaCuOS是一种宽隙p型半导体，与代表性的宽隙半导体相比，具有特殊的性能。我们尝试了不使用La_2S_3合成单相LaCuOS粉末的工艺方法，并报道了La_2S_3和2CuO两种材料联合煅烧的结果。这些结果表明，在较低温度600℃真空条件下制备的样品具有带隙约3.1eV的LaCuOS单相。本文研究了以La_2S_3、CuO和（In_2S_3或Y_2S_3）粉末为原料，采用固相反应法制备了单相in或y掺杂LaCuOS。结合制备的La_<1-x>In_xCuOS和La_<1-x>Y_xCuOS样品的x射线衍射和漫反射光谱结果表明，in和y掺杂的LaCuOS固溶体在x = 0.2左右为单相。in掺杂（x < 0.3）和y掺杂（x < 0.15） LaCuOS的光致发光光谱显示出比未掺杂LaCuOS更高的发射强度。少

(1) Delafossite-type ternary oxides such as CuAlO_2 have received much attention as a material for thermoelectric application and transparent semiconductor. CuLaO_2 is one of delafossites and hence is expected to have valuable properties. The preparation of single-phase CuLaO_2 with delafossite-type structure by means of the solid-state reaction method was investigated. The results showed nearly single-phase CuLaO_2, although a trace amount of metallic copper was included, was obtained by using La(OH)_3, and firing the mixed powder with non-stoichiometric composition ratio of La(OH)_3 : Cu_20 =1 : 1.425 in a vacuum. The CuLaO_2 thus obtained was a p-type semiconductor and has the Seebeck coefficient of 70 μV/K. The single-phase CuLaO_2 was obtained by using La_20_3, and firing the mixed powder with stoichiometric composition ratio in Argon. The emission intensities of samples doped by Sr or Ca were higher of one order than that of non-doped CuLaO_2.[(2)The layered oxysulfide LaCuOS is … More a wide-gap p-type semiconductor that exhibits exceptional properties compared to representative wide-gap semiconductors. We have attempted the process method for synthesizing a single phase of LaCuOS powders not using La_2S_3, and reported by the calcinations from the combination of two materials, La_2S_3 and 2CuO. These results of the samples prepared at the lower temperature of 600℃ under a vacuum showed to have the single phase of LaCuOS with a band gap of about 3.1eV. We have developed for synthesizing a single phase of In-or Y-doped LaCuOS by solid phase reaction method using La_2S_3, CuO and (In_2S_3 or Y_2S_3) powders. The results of X-ray diffraction and diffuse reflective spectroscopy of La_<1-x>In_xCuOS and La_<1-x>Y_xCuOS samples prepared from the combinations showed that the single phase of In-and Y-doped LaCuOS solid solutions below about x = 0.2. These photoluminescence spectra of In-doped (x < 0.3) and Y-doped (x < 0.15) LaCuOS showed to have higher emission intensities than that of non-doped LaCuOS. Less