Nippon Steel Corporation

Kabushiki Kaisha Kobe Seiko Sho

International Superconductivity Technology Center

Hitachi Densen Kabushiki Kaisha

Hirohiko Izumi

Hideki Takeuchi

Shoichi Iwasa

Tadataka Morishita

Katsumi Ohata

Takashi Hase

Yamato Samitsu

Michihiro Yoshinaga

Masatoshi Sakai

In a semiconductor storage device, an access transistor, which has a gate electrode and a pair of impurity diffusion layers, is formed at a device activation region defined by a device isolation structure of a semiconductor substrate. A first insulating film, which has a first contact hole for exposing a portion of the surface of one of the pair of impurity diffusion layers, is formed over the access transistor. A protective film, which has a second contact hole formed on the first contact hole, is formed on the first insulating film. A second insulating film is formed on the side wall faces of the first and second contact holes. A memory capacitor has a lower electrode and an upper part electrode which are opposed each other and are capacitive-coupled through a dielectric film. The lower electrode is filled inside the first and second contact holes to be formed in an island-like shape on the first insulating film through the protective film so as to be electrically connected with the one of the pair of impurity diffusion layers. Each of the first and second contact holes has a diameter which is made smaller by an existence of the second insulating film than a minimum dimension determined by an exposure limit in a photolithography.

Method of fabricating semiconductor storage device having a capacitor

Semiconductor storage device including short circuit avoiding structure and method of fabricating thereof

Surfaces of substrates, typically semiconductor device substrates, are polished with a polishing agent comprising polishing abrasive grains of a metal oxide (e.g. cerium oxide, zirconium oxide or manganese oxide) having a hydrophilic surface and a surface potential (zeta potential) of not more than 50 mV at pH 7 in absolute value, preferably polishing abrasive grains having hydrophilic groups, preferably hydroxyl groups, at the extremities and then cleaned with an aqueous cleaning solution comprising pure water. The polishing abrasive grains remaining on the polished substrate surface can be removed to a satisfactory degree therefrom by simple cleaning using the aqueous cleaning solution only.

Polishing abrasive grains, polishing agent and polishing method

When the surface of a semiconductor device having at least two different films formed on a substrate is flattened by chemical mechanical polishing, the abrasion resistance upon polishing is detected by strain gauges provided close to the surface of the semiconductor device to be polished. In addition, the end of the polishing process is determined on the basis of the amount of change of the detected signals produced from the strain gauges.

Flattening method and apparatus for semiconductor device

A pair of electrically conductive regions of ruthenium dioxide are formed on a BPSG film covering DRAM memory cells arranged in a matrix form. The conductive region is extended in a column direction to be connected to one of impurity diffused regions of MOS transistors of the memory cells at contact holes, and also connected to one of impurity diffused regions of MOS transistors of column direction selection. Formed beneath the conductive region (capacitor upper electrodes) are capacitor lower electrodes connected to the other impurity diffused regions of the memory cell MOS transistors and a high-dielectric film. The conductive region is connected to a (1/2)Vcc power supply. Since the upper electrodes and wiring lines of capacitors can be formed at the same time, the number of steps in a fabrication method can be reduced.

Semiconductor memory device and method for fabricating the same

When a thin metal film is formed on a substrate at a constant substrate temperature by chemical vapor deposition while alternately and discontinuously introducing a raw material gas and a reducing gas onto the substrate, reducing the raw material gas with the reducing gas on the substrate, thereby conducting chemical vapor deposition, and repeating the chemical vapor deposition to obtain a desired film thickness, a thin metal film having a good surface flatness without any current leakage can be obtained without etching the substrate wafer, and when the reducing gas is excited to excited species by an exciting means at the introduction of the reducing gas and the excited species is used be reduce the raw material gas, a lower substrate temperature can be used and chemical vapor deposition process time can be made shorter than without using the exciting means.

Process for forming a thin metal film by chemical vapor deposition

Laser ablation method for forming oxide superconducting films

Growing community of inventors

Tokyo, Japan

Hirohiko Izumi