Abstract: A trench is formed. A first TEOS film is deposited in the trench. Thereafter, the first TEOS film is etched back by a wet etching method up to a planarized surface of a substrate. In this way, seams and a void generated during the first TEOS film deposition step are exposed. This is attained by performing the etching under the conditions that an etching rate for the TEOS film of the upper portion of the trench is larger than that for the TEOS film of the bottom portion of the trench. Thereafter, a second TEOS film is deposited in the trench.

Abstract: A trench is formed. A first TEOS film is deposited in the trench. Thereafter, the first TEOS film is etched back by a wet etching method up to a planarized surface of a substrate. In this way, seams and a void generated during the first TEOS film deposition step are exposed. This is attained by performing the etching under the conditions that an etching rate for the TEOS film of the upper portion of the trench is larger than that for the TEOS film of the bottom portion of the trench. Thereafter, a second TEOS film is deposited in the trench.

Abstract: A highly integrated semiconductor device is made using a high precision manufacturing process having a comparatively small number of process steps. The device is substantially free of misalignment between structures formed with respect to openings formed in the middle of layers. An interlayer insulating film with an opening is formed on a first conductor, and a second conductor is deposited on the resultant structure. Part of the second conductor enters the opening, thereby producing a depression in the second conductor, which has a sharp-angled bottom situated at the horizontal center of the opening. A film made of, for example, a nitride is deposited on the second conductor to fill the depression. Thereafter, this film is removed such that part of it remains in the depression. Using the remaining film as a mask, the second conductor is removed to the same level as the interlayer insulting film.

Abstract: Disclosed is an improved process and liner for trench isolation which includes either a single oxynitride layer or a dual oxynitride (or oxide)/nitride layer. Such a process and liner has an improved process window as well as being an effective O.sub.2 diffusion barrier and resistant to hot phosphoric and hydrofluoric acids.

Abstract: A method for forming a contact is disclosed. A buried impurity region of a second conductivity type is formed in a semiconductor substrate of a first conductivity type. First and second well regions of a first and second conductivity types, respectively, are also formed in the semiconductor substrate. The second well region overlaps the first well region and contacts and surrounds the buried impurity region. A surface impurity concentration of the first well region is greater than a surface impurity concentration of the second well region. A contact to the second well region is formed.

Abstract: Disclosed is an improved process and liner for trench isolation which includes either a single oxynitride layer or a dual oxynitride (or oxide)/nitride layer. Such a process and liner has an improved process window as well as being an effective O.sub.2 diffusion barrier and resistant to hot phosphoric and hydrofluoric acids.

Abstract: In a semiconductor device according to this invention, a first insulating film formed on only a pattern formation conductive film on a semiconductor substrate and having a reflectance which is 25% or more and periodically changes in accordance with a change in film thickness of the first insulating film is formed on the semiconductor substrate. A second insulating film having a reflectance which is 25% or more and periodically changes in accordance with a change in film thickness and having a refractive index different from that of the first insulating film is formed on only the first insulating film. A total reflectance of the first and second insulating films is less than 25%. A photosensitive film is formed on the second insulating film and exposed through a reticle to form a predetermined pattern. Etching is performed using the photosensitive film having this pattern to form a conductive pattern.

Abstract: In a semiconductor device according to this invention, a first insulating film formed on only a pattern formation conductive film on a semiconductor substrate and having a reflectance which is 25% or more and periodically changes in accordance with a change in film thickness of the first insulating film is formed on the semiconductor substrate. A second insulating film having a reflectance which is 25% or more and periodically changes in accordance with a change in film thickness and having a refractive index different from that of the first insulating film is formed on only the first insulating film. A total reflectance of the first and second insulating films is less than 25%. A photosensitive film is formed on the second insulating film and exposed through a reticle to form a predetermined pattern. Etching is performed using the photosensitive film having this pattern to form a conductive pattern.