Rohm Co., Ltd.

Other

Osaka University

Kanto Kagaku Kabushiki Kaisha

Akira Kamisawa

Kiyoto Mori

Taku Yamate

Hayato Katsuragi

Tomonobu Hata

Kimihiro Sasaki

Norikazu Nishiyama

Masaki Takaoka

Yoshiro Fujii

Hiroshi Nozawa

Norifumi Fujimura

Keikichi Tamaru

An electroconductive porous film high in the porosity and strong in the mechanical strength is provided. A mesoporous thin film of the invention, in which a crosslinking structure having a metal phosphate (M&#x2014;PO) skeleton is arranged so as to surround periodically arranged pores, is formed by use of a process that includes: a step of preparing a precursor solution containing phosphoric acid and a surfactant; a step of supplying the precursor solution to a substrate to form a precursor thin film; a step of bringing vapor containing a metal into contact with the precursor thin film obtained in the forming the thin film; a step of reacting the vapor containing a metal and phosphoric acid to form a self-organized thin film; and a step of removing the surfactant from the self-organized thin film.

Mesoporous thin film and method of producing the same

Metal which forms a crystalline insulation layer is sputtered at a target and deposited as a film on a silicon substrate, the metal is chemically combined with reactive gas around the silicon substrate to thereby grow a crystal layer of a crystalline insulation substance, and a voltage is applied to the substrate so that ions of the reactive gas around the substrate are attracted to a surface of the silicon substrate and chemically combined with silicon, whereby an insulation silicon compound layer is formed. As a result, a structure is obtained in which a crystalline insulation layer is formed on a crystalline silicon layer through an amorphous insulation film which is formed by a silicon compound which has an excellent insulation characteristic.

Method for epitaxially growing crystalline insulation layer on crystalline silicon substrate while simultaneously growing silicon oxide, nitride, or oxynitride

Acetylacetone and an aqueous nitric acid are included in a solution in which organic metal compounds of metals constituting a ferroelectric in an organic solvent thereby forming a ferroelectric film formation solution. The solution is applied to a substrate, followed by drying and baking to obtain a ferroelectric film. As a consequence, even when forming a ferroelectric film such as a PZT or PLZT film containing a II group element in the periodic table, a stable ferroelectric film formation solution which prevents neither crystallization nor gelation and is reduced in a change with time in the viscosity thereof can be obtained. A ferroelectric film which contains a II group element and has excellent ferroelectric properties can be thus produced with ease.

Solution for forming ferroelectric film and method for forming ferroelectric film

A ferroelectric material having a basic structure of ReMnO,, said ferroelectric material comprises Re and Mn one of which is contained in excess of the other to a limit of 20 at. % or the ferroelectric material is further added with a 4-valence element. Also, a method of forming a ferroelectric material, comprises decreasing an oxygen partial pressure within a growth reactor such as a vacuum deposition reactor, and forming a film on a film-forming surface of a substrate (,) while blowing an oxidizing source thereto. This structure provides a ferroelectric material low in leak current and improved in ferroelectric characteristics. Where using the material for a semiconductor memory device, its characteristics can be improved.

Ferroelectric material, method of manufacturing the same, semiconductor memory, and method of manufacturing the same

Metal which forms a crystalline insulation layer is sputtered at a target and deposited as a film on a silicon substrate, the metal is chemically combined with reactive gas around the silicon substrate to thereby grow a crystal layer of a crystalline insulation substance, and a voltage is applied to the substrate so that ions of the reactive gas around the substrate are attracted to a surface of the silicon substrate and chemically combined with silicon, whereby an insulation silicon compound layer is formed at the interface of the silicon substrate and the crystalline insulation layer. As a result, a structure is obtained in which a crystalline insulation layer is formed on a crystalline silicon layer with an intervening amorphous insulation film which is formed by a silicon compound which has an excellent insulation characteristic. Hence, it is possible to epitaxially grow an additional semiconductor layer or a crystalline ferroelectric layer on a surface of the crystalline insulation layer, which makes it possible to form a three dimensional semiconductor device, a composite semiconductor device, a high performance semiconductor memory device or the like. Thus, it is possible to obtain a semiconductor device which is new and highly integrated at an inexpensive cost.

Method of forming a crystalline insulation layer on a silicon substrate

Solution for forming ferroelectric film and method for forming

It is an object of the present invention to provide a memory device with processing function using less transistors, and capable of operating with simple operation and allows its operation with less trouble. Each of W cells 34 includes a ferroelectric capacitor CF. One end 40 of the ferroelectric capacitor CF is connected to one of data lines D through a transistor T1. The one end 40 of the ferroelectric capacitor CF is connected to an inner data line MW through a transistor T2. The structure of the Q cells 36 is almost the same as that of the W cells 34. Both readout/writing operations of data from the outside of the device are performed by using the data line D. Data read out from both the W cell 34 and the Q cell 36 is sent to the adder 28 and added thereby, and the resultant data of the addition is written to the Q cell 36 through a buffer circuit 32. The memory device with processing function can be realized with a simple structure by using ferroelectric capacitors CF.

Memory device with processing function

The present invention provides a method for forming a thicker thin film of complex compound easily without causing cracks in the film. Sol solution is coated and dehydrated on an upper surface of a substrate by sol-gel method (step S1, S2). A thin film formed on the upper surface of the substrate is exposed by radiation which has predetermined energy (step S3). Thus, the thin film of complex compound is polymerized, cracks are not caused even in forming a thicker thin film.

Method for forming a thin film of a complex compound

For forming a fine pattern of ferroelectric film without using a resist, a solution containing polyalkoxide having ferroelectric components, as a base part, and functional groups to be activated when exposed to electromagnetic waves or corpuscular beams is used as a pattern forming agent. The pattern form agent is coated onto a substrate, and then electromagnetic or corpuscular beams are radiated thereover to form crosslinks between molecules in the agent. After the crosslinks are cured, the portions devoid of any crosslink and hence uncured are removed using a solvent. Then the molecules associated with the crosslinks remaining on the substrate are then heated to form a ferroelectric crystal.

Agent for forming a fine pattern of ferroelectric film, and method of

Method of forming a fine pattern of ferroelectric film

A ferroelectric memory using ferroelectric capacitors, in which a plurality of electrodes are juxtaposed on each of the two sides of one ferroelectric substance, and the electric fields between the electrodes are controlled, so that more than two different amounts of charges are provided by the ferroelectric capacitors formed by the electrodes. Thereby, the quantity of storage per ferroelectric cell is increased without increase of the cell area.

Ferroelectric memory with multiple-value storage states

A method for patterning a metal oxide thin film comprising the steps of: (1) preparing a mixture solution containing alkoxide or alkoxyalcoholate and alcohol or alkoxyalcohol, (2) mixing an acid-generating agent with the mixture solution, (3) applying the mixture solution to a substrate to form a thin film and drying the thin film, (4) selectively irradiating the thin film formed on the substrate to accelerate the gelation, (5) removing the non-irradiated thin film, and (6) burning the remaining thin film. According to the present invention, a metal oxide thin film is formed by sol-gel method, and thereto is mixed an acid-generating agent, so that etching by irradiating can be applied to a precursor thin film not sintered. Thanks to this, a metal oxide thin film can be easily patterned with a fine processing.

Growing community of inventors

Kyoto, Japan

Akira Kamisawa