A composition for resist underlayer film formation, containing a compound represented by the following formula (1).

[L.sub.xTe(OR.sup.1).sub.y](1)

(In the above formula (1), L is a ligand other than OR.sup.1; R.sup.1 is any of a hydrogen atom, a substituted or unsubstituted, linear alkyl group having 1 to 20 carbon atoms or branched or cyclic alkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms and a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms; x is an integer of 0 to 6; y is an integer of 0 to 6; the total of x and y is 1 to 6; when x is 2 or more, a plurality of L may be the same or different; and when y is 2 or more, a plurality of R.sup.1 may be the same or different.)

A method for making MnBi.sub.2Te.sub.4 single crystal is provided. The method includes: providing a mixture of polycrystalline MnTe and polycrystalline Bi.sub.2Te.sub.3 in Molar ratio of 1.1:11:1.1; heating the mixture in a vacuum reaction chamber to 700 C.900 C., cooling the mixture to 570 C.600 C. slowly with a speed less than or equal to 1 C./hour, and annealing the mixture at 570 C.600 C. for a time above 10 days to obtain an intermediate product; and air quenching the intermediate product from 570 C.600 C. to room temperature. The method for making MnBi.sub.2Te.sub.4 single crystal is simple and has low cost.

The invention relates to a solid ionic conductor for a rechargeable non-aqueous electrochemical battery cell having the stoichiometric formula K(ASXX).sub.pq SO.sub.2, where K represents a cation from the group of the alkali metals with p=1, of the alkaline-earth metals with p=2 or of the zinc group with p=2, A represents an element from the third main group, S represents sulfur, selenium or tellurium, X and X represent a halogen, and the numerical value q is greater than 0 and less than or equal to 100.

A method for preparing a magic-sized nano-crystalline substance, wherein a component containing at least one metal element of groups IIB, IIIA and IVA in the periodic table, and a component containing at least one non-metal element of groups VIA and VA are used as raw materials. In a reaction system for preparing a conventional nano-crystalline substance and in an inert gas atmosphere, after heating the reaction, reactants are cooled to a temperature 50% lower than the actual heating temperature of the reaction thereof, and after standing, the target product of the magic-sized nano-crystalline substance is obtained. The required pure target product can be obtained by the preparation method.

A chalcogenide material and an electronic device are provided. The chalcogenide material may include 0.1-5 atomic percent (at %) of silicon, 15-22 at % of germanium, 30-35 at % of arsenic and 40-50 at % of selenium. The electronic device may include a semiconductor memory device, the semiconductor memory device including a first memory cell that includes a first switching element. The first switching element may include a chalcogenide material including 0.1-5 atomic percent (at %) of silicon, 15-22 at % of germanium, 30-35 at % of arsenic, and 40-50 at % of selenium.

A chalcogen-containing compound of the following Chemical Formula 1 which exhibits excellent phase stability at a low temperature, particularly at a temperature corresponding to the driving temperature of a thermoelectric element, and also exhibits an excellent thermoelectric performance index through an increase in a power factor and a decrease in thermal conductivity, a method for preparing the same, and a thermoelectric element including the same:

V.sub.1-xM.sub.xSn.sub.4Bi.sub.2Se.sub.7-yTe.sub.y [Chemical Formula 1]

In the above Formula 1, V is a vacancy, M is an alkali metal, x is greater than 0 and less than 1, and y is Greater than 0 and less than or equal to 1.

The present invention relates to a method of producing metal nanoparticles and metal sulfide nanoparticles using a recombinant microorganism co-expressing metallothionein and phytochelatin synthase, which are heavy metal-adsorbing proteins, and to the use of metal nanoparticles and metal sulfide nanoparticles synthesized by the method. The present invention provides a method for synthesizing metal nanoparticles which have been difficult to synthesize by conventional biological methods. The present invention makes it possible to synthesize metal nanoparticles in an environmentally friendly and cost-effective manner, and also makes it possible to synthesize metal sulfide nanoparticles. In addition, even metal nanoparticles which could have been produced by conventional chemical or biological methods are produced in a significantly increased yield by use of the method of the present invention.

A method for making MnBi.sub.2Te.sub.4 single crystal is provided. The method includes: providing a mixture of polycrystalline MnTe and polycrystalline Bi.sub.2Te.sub.3 in Molar ratio of 1.1:11:1.1; heating the mixture in a vacuum reaction chamber to 700 C.900 C., cooling the mixture to 570 C.600 C. slowly with a speed less than or equal to 1 C./hour, and annealing the mixture at 570 C.600 C. for a time above 10 days to obtain an intermediate product; and air quenching the intermediate product from 570 C.600 C. to room temperature. The method for making MnBi.sub.2Te.sub.4 single crystal is simple and has low cost.

Disclosed is a plastic semiconductor material and a preparation method thereof. The semiconductor material comprises an argentite-based compound represented by the following formula (I): Ag.sub.2-X.sub.S.sub.1-Y.sub.(I), in which 0<0.5, 0<0.5, Xis at least one of Cu, Au, Fe, Co, Ni, Zn, Ti, or V, and Y is at least one of N, P, As, Sb, Se, Te, O, Br, Cl, I, or F. The material can withstand certain deformations, similar to organic materials, and has excellent semiconductor properties with adjustable electrical properties, thereby enabling the preparation of high-performance flexible semiconductor devices.

Cesium-niobium-chalcogenide compounds and a semiconductor device are provided. The cesium-niobium-chalcogenide compound is selected from the group consisting of CsNbS.sub.3, CsNbSe.sub.3, and CsNbO.sub.x-3Q.sub.x, where Q is S or Se, and x is 1 or 2, and includes an edge-shared orthorhombic crystal structure. In one embodiment, the semiconductor device includes a cathode layer, an anode layer, and an active layer disposed between the cathode layer and the anode layer, and the active layer includes the cesium-niobium-chalcogenide compound.