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The effects of Al2O3 dopings in pseudobinary (In2O3)1-δ(2ZnO)δ films were investigated, and carrier generation mechanism was discussed. Here the δ value is the ratio of Zn/(Zn+In). For Al2O3 doping below 2 wt%, low-resitivity amorphous films in 2–4×10-4 Ω cm were deposited over a narrow range of δ=Zn/(Zn+In) (0.2⩽δ⩽0.4). At Al2O3=2 wt% doping, the resistivity was improved in the same narrow range of δ. Using a ZnO:Al target with 3 wt% Al2O3, film resistivities of 2–4×10-4 Ω cm were attained over a relatively wide range of δ in the amorphous phase (0.2⩽δ⩽0.6). This result was due to the increase in carrier concentration at δ=0.3–0.6. The Al2O3 doping also influenced on optical band gap: band gap shrinkage for Al2O3=2 wt% and band gap widening for Al2O3=3 wt%. For homologous crystalline films, Al2O3 doping decreased carrier concentration, independent of the level of Al2O3 doping. The Al2O3 doping increased linearly optical band gap energy. These results indicate that the Al atoms are impurities that distort the lattice in homologous film. [Copyright &y& Elsevier]

Abstract: Magnetic properties under pressure have been investigated on the weak itinerant electron ferromagnet Rh2NiGe. The pressure derivative of the Curie temperature T C has been obtained from the results of the temperature dependence of the initial permeability under pressure up to 10kbar. The value of dT C/dp is found to be −0.60K/kbar. The pressure change of the spontaneous magnetization σ s at 4.2K for Rh2NiGe has been determined by the subtraction method under pressure up to 10kbar. The value of dσ s/dp is found to be −0.014emu/gkbar. The obtained results are analyzed using the spin fluctuation theory. [Copyright &y& Elsevier]

Abstract: Rh2NiGe crystallizes in Heusler L21 structure. Precise magnetization measurements have been made on Rh2NiGe. The spontaneous magnetic moment at 4.2K and the Curie temperature T C are 0.57μ B/f.u. and 113K, respectively. Below 30K the decrease in the square of the spontaneous magnetization σ s(T)2 is proportional to T 2. However, over a temperature range from 89K to the Curie temperature the decrease in σ s(T)2 is proportiona to T 4/3. The obtained results are analyzed using spin fluctuation theory. [Copyright &y& Elsevier]

Thin ZnO–SnO2 films were deposited on glass substrates by opposed planar magnetron sputtering, in which ZnO and SnO2:Sb (Sb2O5 3 wt% doped) targets face each other. Glass substrate temperatures (Ts) were held at 150°C and 250°C. As an experimental parameter, current ratio δ, ZnO target current divided by the sum of ZnO and SnO2 target currents, was used. Compositions of as-deposited film were changed with the current ratio δ. Amorphous transparent films appeared over the range of 0.47⩽δ⩽0.80 (Zn/(Zn+Sn)=0.28–0.76) at Ts=150°C, over the range of 0.33⩽δ⩽0.73 (Zn/(Zn+Sn)=0.32–0.66) at Ts=250°C. Crystalline ZnSnO3 and crystalline Zn2SnO4 was not obtained in any of the as-deposited films, even at δ=0.62 (Zn/(Zn+Sn)=1/2) or δ=0.73 (Zn/(Zn+Sn)=2/3). Amorphous films exist as form of (ZnSnO3)1-x(SnO2)x over the range of 0.50⩽δ⩽0.62 (0⩽x⩽0.5) and (ZnSnO3)1-y(ZnO)y over the range of 0.62⩽δ⩽0.73 (0⩽y⩽0.5). The minimum resistivity of the deposited amorphous films was 3.6 ×10-2 Ω cm at δ=0.50 (Zn/(Zn+Sn) =0.33), Ts=250°C. [Copyright &y& Elsevier]