Abstract: Provided is a semiconductor memory device in which defective contact, deterioration in transistor characteristics and other problems are solved with a thermally stable, conductive diffusion barrier layer against oxygen, and against constituent elements in a plug material and a lower electrode, formed at the interface between a plug and the lower electrode made of a noble metal. The semiconductor memory device comprises a dielectric capacitor of a stacked structure including a first electrode (a lower electrode), a dielectric film and a second electrode (an upper electrode) and a conductive plug connected to the lower electrode, wherein the lower electrode connected to the conductive plug includes a metal suboxide layer with conductiveness and a diffusion barrier layer blocking diffusion of oxygen, and the metal suboxide layer and the diffusion barrier layer are stacked in the order from the conductive plug side of the lower electrode.

Abstract: Vapors normally arising within a standing gasoline tank are captured in a charcoal filled cannister. When the engine is running, air is drawn through the cannister thereby purging gasoline adsorbed on the charcoal within the cannister and delivering the purged gasoline vapors to the carburetor ultimately for combustion within the engine. Interference by the presence of such accumulated gasoline vapors in the carburetor, particularly during warm restarts and idling, can be avoided by preventing the injection of these gasoline vapors into the carburetor at the inappropriate times.

Abstract: The present invention is to provide a method for manufacturing a semiconductor device of high efficiency and high integration density. The method for manufacturing a semiconductor device comprises the steps of forming semiconductive layers (30), (31) and (31') having on the surface thereof a concave portion, forming a nitride layer (35) within the concave portions forming with the nitride layer (35) as a mask an oxide layer (39) on the surface of the semiconductive layer (30), removing said nitride layer (35) and introducing an impurity into the semiconductive layers (31) and (31') with the oxide layer (39) as a mask. In accordance therewith, the elements can be made finer and hence the method of this invention is suitable for manufacturing an IC device high in efficiency and high in integration density.

Abstract: Utilizing the fact that an isotropic etching rate of a semiconductor layer such as a polycrystalline or amorphous silicon layer depends on a doped amount of an impurity doped into the semiconductor layer, the impurity is doped into a semiconductor layer (26) formed on a substrate (4) so as to have a concentration distribution in its thickness direction. Then, in a region of the semiconductor layer (26) to be selectively removed, an anisotropic etching is carried out such that a portion of high impurity concentration is removed and a portion thereof in the thickness direction is remained. Thereafter, the remained portion is subjected to an isotropic etching to thereby suppress the side etching.