Proposed are a layered Group III-V compound containing phosphorus, a Group III-V nanosheet that may be prepared using the same, and an electrical device including the materials. There is proposed a layered compound represented by [Formula 1] M.sub.x-mA.sub.yP.sub.z (Where M is at least one of Group II elements, A is at least one of Group III elements, x, y, and z are positive numbers which are determined according to stoichiometric ratios to ensure charge balance when m is 0, and 0<m<x).

Provided is an indium phosphide substrate, a semiconductor epitaxial wafer, and a method for producing an indium phosphide substrate, which can satisfactorily suppress warpage of the back surface of the substrate. The indium phosphide substrate includes a main surface for forming an epitaxial crystal layer and a back surface opposite to the main surface, wherein the back surface has a SORI value of 2.5 μm or less, as measured with the back surface of the indium phosphide substrate facing upward.

The silyl phosphine compound of the present invention is represented by the formula (1) and has an arsenic content of not more than 1 ppm. The process for producing a silyl phosphine compound of the present invention is a process comprising mixing a basic compound, a silylating agent and phosphine to obtain a solution containing a silyl phosphine compound, removing a solvent from the solution to obtain a concentrated solution of a silyl phosphine compound, and distilling the concentrated solution, wherein an arsenic content in the phosphine is adjusted to not more than 1 ppm by volume in terms of arsine. The process for producing InP quantum dots of the present invention uses, as a phosphorus source, a silyl phosphine compound represented by the formula (1) and having an arsenic content of not more than 1 ppm by mass.

##STR00001##

(For definition of R, see the specification.)

The invention relates to InP-based nanoclusters that include indium and phosphorus and further include zinc, chlorine, or a combination thereof, and to a method of preparing the InP-based nanoparticles including heating the InP-based nanoclusters in the presence of zinc, chlorine, or a combination thereof.

A method for preparing semiconductor nanocrystals is disclosed. The method includes adding one or more cation precursors and one or more anion precursors in a reaction mixture including a solvent in a reaction vessel, maintaining the reaction mixture at a first temperature and for a first time period sufficient to produce semiconductor nanocrystal seed particles of the cation and the anion, and maintaining the reaction mixture at a second temperature that is higher than the first temperature for a second time period sufficient to enlarge the semiconductor nanocrystal seed particles to produce semiconductor nanocrystals from the cation and the anion.

Provided is an indium phosphide substrate, a semiconductor epitaxial wafer, and a method for producing an indium phosphide substrate, which can satisfactorily suppress warpage of the back surface of the substrate. The indium phosphide substrate includes a main surface for forming an epitaxial crystal layer and a back surface opposite to the main surface, wherein the back surface has a BOW value of −2.0 to 2.0 μm, as measured with the back surface of the indium phosphide substrate facing upward.

Methods of synthesizing colloidal ternary Group III-V nanocrystals are provided. Also provided are the colloidal ternary Group III-V nanocrystals made using the methods. In the methods, molten inorganic salts are used as high temperature solvents to carry out cation exchange reactions that convert binary nanocrystals into ternary nanocrystals.

Provided is a semiconductor nanoparticle complex in which a ligand is coordinated to a surface of a semiconductor nanoparticle. The semiconductor nanoparticle includes In and P, the ligand includes a mercapto fatty acid ester represented by the following general formula, and the mercapto fatty acid ester has an SP value of 9.30 or less.

General formula: HS—R.sub.1—COOR.sub.2 (where R.sub.1 is a C.sub.1-11 hydrocarbon group and R.sub.2 is a C.sub.1-30 hydrocarbon group). The present invention can provide a semiconductor nanoparticle complex that keeps high fluorescence quantum yield before and after purification.

Tetrapod-shaped quantum dots having a tetrapod shape in which a core includes a plurality of arms, and each of the arms have a different growth degree depending on the crystal direction.

The present invention relates to a method for producing an InP-based quantum dot precursor from a phosphorus source and an indium source, in which a silylphosphine compound represented by the following Formula (1) with a content of a compound represented by the following Formula (2) of 0.3 mol % or less is used as the phosphorus source. Further, the present invention provides a method for producing an InP-based quantum dot comprising heating an InP quantum dot precursor to a temperature of 200° C. or more and 350° C. or less to obtain an InP quantum dot.

##STR00001##

(R is as defined in the specification.)