Abstract: A method of figuring an exposure energy. A required exposure energy is calculated according to a critical dimension (CD) of an exposing layer. A first CD deviation is obtained from a layer before the exposing layer. From the first CD deviation, a first energy compensation is calculated. Whether the deviation of photoresist sensitivity of two sequential batches is less than 1% is checked. If the deviation of photoresist sensitivity of two sequential batches is less than 1%, a sum of the required exposure energy and the first energy compensation is the exposure energy applied to the exposing layer. Otherwise, a second CD deviation is commutated according to the deviation of photoresist sensitivity of two sequential batches. A second energy compensation is then obtained from the second CD deviation, and a sum of the required exposure energy and the first/second energy compensation is the exposure energy applied to the exposing layer.

Abstract: A polycide wiring layer constituted by a polysilicon film and a silicide film is used as a bit line of a DRAM. When a memory cell region having an n-type impurity diffusion layer and a peripheral circuit region having a p-type impurity diffusion layer are to be electrically connected through the polysilicon film, a diffusion prevention film consisting of TiSiN or WSiN is formed as an underlying film of the polysilicon film. With this diffusion prevention film, interdiffusion between the n- and p-type impurity diffusion layers can be prevented. In addition, heat resistance at 900.degree. C. or more can be obtained in processes after formation of the diffusion prevention film.

Abstract: Redundant memory portions having redundant memory cells for relieving malfunctioning normal memory cells are arranged among the semiconductor memory portions that neighbor each other in the row direction and in the column direction on a semiconductor wafer on which a plurality of semiconductor memory portions are arranged in the form of a matrix. Cutting lines are formed between the redundant memory portions and the neighboring semiconductor memory portions, so that the semiconductor wafer can be separated into semiconductor memory devices (chips) in a subsequent stage in a manner in which the redundant memory portions are connected to the semiconductor memory portion as required. This embodiment makes it possible to decrease the chip size and to efficiently substitute the redundant memory cell array for the defective lines.

Abstract: A method of fabricating a semiconductor device, comprises the steps of forming a trench in a semiconductor substrate by using a selective etching process; forming an insulating layer at least on the inner surface of the trench; forming a film containing silicon at least on the insulation layer in the trench and doping a first impurity of a first conductivity type by a first ion implantation to a predetermined depth of the semiconductor substrate at least through the film containing silicon, and wherein the first impurity doped into the semiconductor substrate by the first ion implantation is at a level deeper than the bottom of the trench.

Abstract: A method for forming shallow trench isolation without a recessed edge problem is disclosed. The present invention comprises forming a pad oxide layer on a substrate. Next, a silicon nitride layer is formed on the pad oxide, and a sacrificial layer is formed on the silicon nitride layer. A photo-resist layer that defines an active region on the sacrificial layer is applied. Thereafter, the portions of the sacrificial layer, the silicon nitride layer, the pad oxide layer and the substrate are removed to form a trench. Portions of the silicon nitride layer are undercut, and a dielectric layer is formed to fill the trench. The dielectric layer is planarized until the silicon nitride layer is exposed. Finally, the silicon nitride layer and the pad oxide layer are removed.