Kabushikikaisha Kojundokagaku Kenkyusho

Tokyo Electron Limited

Yoshinori Kuboshima

Hidekimi Kadokura

Shintaro Higashi

Yumiko Kawano

Masakatsu Shibasaki

Shigeki Matsunaga

Yumie Okuhara

Masamichi Matsumoto

Tadashi Ishii

Hiroshi Matsumoto

Takayuki Mogi

Kaoru Kikukawa

Provided are a novel europium compound which has a melting point of 180&#xb0; C. or lower and can be stably supplied by bubbling in a chemical vapor deposition method or an atomic layer deposition method, a precursor for forming a europium-containing thin film based on the compound, and a method for forming a europium-containing thin film using this precursor. A europium-containing thin film is formed using bis(tetramethylmonoalkylcyclopentadienyl)europium as a precursor for forming a europium-containing thin film by a chemical vapor deposition method or anatomic layer deposition method.

Precursor for formation of europium-containing thin film, and method for forming europium-containing thin film

The present invention provides a process for forming a strontium-containing thin film of a cyclopentadienyl-based strontium compound, which is in the liquid state at room temperature to 50&#xb0; C., can be purified by distillation, present as a monomer, has high vapor pressure, and suitable for mass production. bis(propyltetramethylcyclopentadienyl)strontium is used as an Sr source to form a strontium-containing thin film such as a SrTiOfilm, a (Ba, Sr)TiOfilm by chemical vapor deposition or atomic layer deposition.

Process for forming the strontium-containing thin film

Provided is a method for synthesizing a rare-earth oxo isopropoxide safely with a high yield, using a rare-earth metal, which is more inexpensive than anhydrous rare-earth chlorides, as a raw material. In a solvent containing 90% or more by weight of isopropyl alcohol, a rare-earth metal and isopropyl alcohol are caused to react with each other in the presence of a mercury compound catalyst, a solvent is added thereto or the solvent is partially replaced, and then in a solvent containing 25% or more by weight of an aromatic hydrocarbon solvent having 6 to 10 carbon atoms or a saturated hydrocarbon solvent having 5 to 12 carbon atoms, water is added to conduct partial hydrolysis reaction, thereby synthesizing a rare-earth oxoisopropoxide.

Method for synthesizing rare-earth oxo isopropoxide

The present invention provides a raw material for forming a strontium-containing thin film of a cyclopentadienyl-based strontium compound, which is in the liquid state at room temperature to 50&#xb0; C., can be purified by distillation, present as a monomer, has high vapor pressure, and suitable for mass production, and a process for preparing the same. Sr[C(CH)(CH)]is prepared by reacting Na[C(CH)(CH)]or K[C(CH)(CH)]with SrIin THF to produce a THF adduct of Sr[C(CH)(CH)]; evaporating THF and extracting the residue with toluene to give a toluene solution; evaporating toluene and drying the residue under reduced pressure; and heating to 100 to 160&#xb0; C. in vacuo to dissociate and remove THF and distilling.

Raw material for forming a strontium-containing thin film and process for preparing the raw material

This invention provides a method of evaluating the catalytic activity of a rare earth alkoxide used as a starting material of a basic catalyst or an asymmetric synthesis catalyst. The rare earth alkoxide used as the subject of evaluation and 2,2'-dihydroxy-1, 1&#x2032;-binaphthol are used as the starting material to prepare a rare earth complex catalyst which is then used to conduct the asymmetric epoxidation of an enone. The epoxy enone formed by this reaction, the unreacted enone, and the enantiomeric excess are measured, and from these results, the catalytic activity of the rare earth alkoxide is evaluated.

Method of evaluating the catalytic activity of a rare earth alkoxide

The invention provides true La(OiPr)preferable as a starting material for an asymmetric synthesis catalyst and a process for producing the same. In this process, anhydrous lanthanum chloride LaClis reacted with potassium isopropoxide K(OiPr) in a mixed solvent of isopropanol and toluene, then the isopropanol is distilled away to replace all the solvent by toluene, then the reaction solution is left, decanted and filtered to give a transparent filtrate, and the solvent is distilled away from the filtrate which is then vacuum-dried under heating, whereby high-purity La(OiPr)is obtained in 77% yield. In this high-purity La(OiPr), the La content is 97 to 103% of the theoretical content, impurity K is 0.3% or less, (Li+Na) is 0.01% or less, Cl is 0.2% or less, and the degree of association thereof is 5.5 to 6.5.

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Tokyo, Japan

Yoshinori Kuboshima