Flexible high-efficiency CZTSSe solar cells on stainless steel substrates

Stainless steel (SS) foil is made of abundant materials and is a durable and flexible substrate, but the efficiency of a solar cell on SS foil deteriorates via the diffusion of impurities from the SS substrate into a Cu2ZnSn(S,Se)4 (CZTSSe) absorber layer.

Spectral Dependence of Optical Absorption of 4H-SiC Doped with Boron and Aluminum

Optical absorption of p-n-4H-SiC structures doped with boron and aluminum by low-temperature diffusion was studied for the first time. Diffusion of impurities was performed from aluminum-silicate and boron-silicate films (sources) fabricated by various methods. In the spectral dependences of optical absorption at room temperature, bands associated with transitions from impurity levels, as well as absorption bands associated with defects of the vacancy nature, were observed. The level of absorption in the samples was used to estimate concentration of defects. It was shown that the use of sources of impurity atoms created by using boron and aluminum chlorides allows one to reduce the concentration of vacancy defects.

Self-Consolidation Mechanism of Ti5Si3 Compact Obtained by Electro-Discharge-Sintering Directly from Physically Blended Ti-37.5 at.% Si Powder Mixture

Characteristics of electro-discharge-sintering of the Ti-37.5at.% Si powder mixture was investigated as a function of the input energy, capacitance, and discharge time without applying any external pressure. A solid bulk of Ti5Si3was obtained only after in less than 129 μsec by the EDS process. During a discharge, the heat is generated to liquefy and alloy the particles, and which enhances the pinch pressure can condensate them without allowing a formation of pores. Three step processes for the self-consolidation mechanism during EDS are proposed; (a) a physical breakdown of oxide film on elemental as-received powder particles, (b) alloying and densifying the consolidation of powder particles by the pinch pressure, and (c) diffusion of impurities into the consolidated surface.

Solutions modeling of nonlinear equation of diffusion for three dimensions case

We have made a practical consideration of an important case of nonlinear diffusion of impurities in a three-dimensional case through square window in the x, y plane for the production of electronic devices and evaluation of its parameters. The nonlinear diffusion coefficients for diffusion in x, y, z directions are proportional to the concentration of impurities. The three-dimensional nonlinear diffusion equation was transformed using similarity variables. The approximate analytical solution of the transformed equation expressed by Taylor series approximate expansion for three similarity variables about the maximum impurities penetration points in x, y, z axes including the square terms.