Abstract: To form a silicide layer excellent in flatness, uniform in film thickness, and less in junction leak, by destroying the natural oxide film which adversely affects a formation of silicide layer of cobalt or nickel. A cobalt layer (7) is formed in a film thickness of 20 nm or less on an electrode layer (4A) of a gate electrode (4) and on source/drain diffusion layers (1, 2), and a nitrogen (8) is injected by the ion implantation at a density of about 1E15/cm.sup.3 with an injection energy of 10 keV or more. At this time, the nitrogens (8) destroy the natural oxide film existing in the interface of the cobalt layer (7) and electrode layer (4A), and in the interface of the cobalt layer (7) and the source/drain diffusion layers (1, 2), and distribute deeply into the electrode layer (4A) and the source/drain diffusion layers (1, 2). Later, by a silicide forming reaction of cobalt, a silicide layer (6) is formed. Since the natural oxide film does not exist, the silicide forming reaction proceeds uniformly.

Abstract: To obtain a semiconductor device which prevents an increase in the resistance of a source/drain region; which operates fast and stably; and which provides a high manufacturing yield, and to obtain a method of manufacturing the semiconductor device. A recess 8 is formed on a first low impurity-concentration region 5 with the exception of the area immediately below side wall insulating material 6y, and a layer damaged as a result of formation of the side wall insulating material 6y is removed. Further, a second low impurity-concentration region 10 is formed below the recess 8.

Abstract: The present invention provides a semiconductor device which includes trench-type element isolation which performs accurate alignment without deteriorating a device capability, and a method of manufacturing such a semiconductor device. Since a dummy gate electrode (14A) is formed in an edge proximity region of a trench (10A), a structure which does not create an etching remainder is realized. In addition, since a height difference is provided in a surface of the dummy gate electrode (14A) in such a manner that the height difference reflects a preliminary height difference between a surface of a silicon oxide films (2A) and a surface of a silicon substrate (1), it is possible to use the dummy gate electrode itself (14A) as an alignment mark.

Abstract: A gate electrode is made up of a polycrystalline silicon film containing phosphorous as a dopant for determining its conductivity type, a titanium silicide film of the C54 structure, and a tungsten silicide film all of which films are laid one on another in said order.

Abstract: In a complementary MOS field effect transistor having a dual gate electrode structure, which is improved so that an element property can be enhanced, a first gate electrode of an n channel MOSFET includes a first barrier film, and a second gate electrode of a p channel MOSFET includes a second barrier film. The first barrier film has a sufficiently small thickness so that a potential can be transmitted from a first conductive film to a first polycrystalline silicon film by means of a tunnel effect. The second barrier film has a sufficiently small thickness so that a potential can be transmitted from a second conductive film to a second silicon film by means of a tunnel effect.

Abstract: To form a silicide layer excellent in flatness, uniform in film thickness, and less in junction leak, by destroying the natural oxide film which adversely affects a formation of silicide layer of cobalt or nickel. A cobalt layer (7) is formed in a film thickness of 20 nm or less on an electrode layer (4A) of a gate electrode (4) and on source/drain diffusion layers (1, 2), and a nitrogen (8) is injected by the ion implantation at a density of about 1E15/cm.sup.3 with an injection energy of 10 keV or more. At this time, the nitrogens (8) destroy the natural oxide film existing in the interface of the cobalt layer (7) and electrode layer (4A), and in the interface of the cobalt layer (7) and the source/drain diffusion layers (1, 2), and distribute deeply into the electrode layer (4A) and the source/drain diffusion layers (1, 2). Later, by a silicide forming reaction of cobalt, a silicide layer (6) is formed. Since the natural oxide film does not exist, the silicide forming reaction proceeds uniformly.

Abstract: A semiconductor device in which ability for isolating elements from each other can be improved and increase in substrate constant and junction capacitance can be suppressed, is disclosed. An impurity layer for improving the ability for isolating elements is positioned only immediately below an isolating insulating film. An impurity layer for adjusting substrate constant and junction capacitance is formed through independent steps from the impurity layer for improving the isolating ability.

Abstract: A semiconductor memory device and a manufacturing method of the same can effectively prevent deterioration of endurance characteristic which may occur in a data erasing operation, and a drain disturb phenomenon which may occur in a data writing operation. In the semiconductor memory device, an N-type impurity layer 3 is formed on a main surface of a P-type silicon substrate 1 located in a channel region. Thereby, a high electric field is not applied to a boundary region between the N-type impurity layer 3 and an N-type source diffusion region 10 during erasing of data, so that generation of interband tunneling in this region is effectively prevented. Also in this semiconductor memory device, the drain diffusion region 9 has an offset structure in which no portion thereof overlaps the floating gate electrode 5.

Abstract: An oxynitride film whose compositional ratio between oxygen and nitrogen varies in the thickness direction thereof is formed on a main surface of a silicon substrate, on which a silicon nitride film is formed. The oxynitride film is so controlled in composition that said film has a portion near the silicon substrate which has a composition close to that of a silicon oxide film and that said film has a composition closer to that of a silicon nitride film toward the silicon nitride film. The silicon nitride film and the oxynitride film are patterned in a desired form. Using the patterned silicon nitride film and oxynitride film as a mask, the main surface of the silicon substrate is thermally oxidized. The use of the oxynitride film whose composition varies in the thickness direction thereof can suppress bird's beak extension of an element isolation oxide film and also formation of crystal defects in the main surface of the silicon substrate.

Abstract: A semiconductor device includes a buried impurity layer formed at a predetermined depth from a main surface of a semiconductor substrate by utilizing ion injection of a conductivity type determining element, and a gettering layer formed in a position adjacent to and not shallower than the buried impurity layer by utilizing ion injection of an element other than a conductivity type determining element.

Abstract: A semiconductor device includes a buried impurity layer (3) formed at a predetermined depth from a main surface of a semiconductor substrate (1) by utilizing ion injection of a conductivity type determining element, and a gettering layer (2) formed in a position adjacent to and not shallower than the buried impurity layer (3) by utilizing ion injection of an element other than a conductivity type determining element.

Abstract: A semiconductor device in which ability for isolating elements from each other can be improved and increase in substrate constant and junction capacitance can be suppressed, is disclosed. An impurity layer for improving the ability for isolating elements is positioned only immediately below an isolating insulating film. An impurity layer for adjusting substrate constant and junction capacitance is formed through independent steps from the impurity layer for improving the isolating ability.

Abstract: The present invention aims to prevent formation of a bird's beak and a bird's head in forming a miniaturized element isolation oxide film, and to suppress introduction of a defect into a silicon substrate. A first silicon oxide film is formed on the surface of a silicon substrate. A polycrystalline silicon film and a first silicon nitride film having an opening are formed on surface of the first silicon oxide film. A second silicon oxide film is deposited on the surface of the first silicon oxide film and the first silicon nitride film so as to cover the inner wall of the opening by a CVD method. A second silicon nitride film formed to cover the surface of the second silicon oxide film is subjected to anisotropical etching, whereby a sidewall nitride film is formed on the surface of the second silicon oxide film so as to cover the sidewall of the opening. With the sidewall nitride film as a mask, an element isolation film is formed at the bottom of the opening.

Abstract: A semiconductor device includes a p-type silicon substrate, a first well of p-type formed in a major surface of the silicon substrate, and a second well of n-type formed close to the first well in the major surface of the silicon substrate. A third well of p-type is formed inside the second well and, furthermore, a conductive layer including p-type impurities of higher concentration than that of the first well is formed as extending immediately below both the first well and the second well. In accordance with this structure, even if minority carriers are injected, they recombine and disappear in the conductive layer, so that the implantation of the carriers into the first well is prevented. As a result, various disadvantageous phenomena due to the injection of the minority carriers are prevented and a semiconductor device having a stable device characteristic and high integration density is provided.

Abstract: A semiconductor memory device and a manufacturing method of the same can effectively prevent deterioration of endurance characteristic which may occur in a data erasing operation, and a drain disturb phenomenon which may occur in a data writing operation. In the semiconductor memory device, an N-type impurity layer 3 is formed on a main surface of a P-type silicon substrate 1 located in a channel region. Thereby, a high electric field is not applied to a boundary region between the N-type impurity layer 3 and an N-type source diffusion region 10 during erasing of data, so that generation of interband tunneling in this region is effectively prevented. Also in this semiconductor memory device, the drain diffusion region 9 has an offset structure in which no portion thereof overlaps the floating gate electrode 5.

Abstract: The present invention is mainly characterized in that a semiconductor device having a well which is of the same conductivity type as that of a substrate and which is isolated from the substrate is improved not to cause interference between the well and the substrate even if a large amount of minority carriers are implanted. The semiconductor device is provided with a semiconductor substrate of the first conductivity type having the main surface. A first well of a first conductivity type is provided in the main surface of the semiconductor substrate. The first well, having side portions and a bottom portion, extends from the main surface. A second well of a second conductivity type is provided in the main surface of the semiconductor substrate so as to surround the side portions and the bottom portion of the first well. The bottom portion of the second well has a crystal defect region.

Abstract: A semiconductor device includes a p-type silicon substrate, a first well of p-type formed in a major surface of the silicon substrate, and a second well of n-type formed close to the first well in the major surface of the silicon substrate. A third well of p-type is formed inside the second well and, furthermore, a conductive layer including p-type impurities of higher concentration than that of the first well is formed as extending immediately below both the first well and the second well. In accordance with this structure, even if minority carriers are injected, they recombine and disappear in the conductive layer, so that the implantation of the carriers into the first well is prevented. As a result, various disadvantageous phenomena due to the injection of the minority carriers are prevented and a semiconductor device having a stable device characteristic and high integration density is provided.

Abstract: A semiconductor device having a reduced leakage current is fabricated in a short time at a low cost with excellent controllability. A buried layer (20) which includes a principal buried layer (21) of high ion concentration containing secondary defects (22) sandwiched between secondary buried layers (3a, 3b) of low ion concentration from upper and lower directions is formed on a semiconductor substrate (1). The secondary defects (22) have stable gettering effects for reducing defects caused during formation of a transistor (200) and contamination by heavy metals. Further, the secondary buried layers (3a, 3b) prevent depletion layers from reaching the secondary defects (22). The semiconductor device can be formed in a short time since no epitaxial growth is employed.

Abstract: A semiconductor device having a reduced leakage current is fabricated in a short time at a low cost with excellent controllability. A buried layer (20) which includes a principal buried layer (21) of high ion concentration containing secondary defects (22) sandwiched between secondary buried layers (3a, 3b) of low ion concentration from upper and lower directions is formed on a semiconductor substrate (1). The secondary defects (22) have stable gettering effects for reducing defects caused during formation of a transistor (200) and contamination by heavy metals. Further, the secondary buried layers (3a, 3b) prevent depletion layers from reaching the secondary defects (22). The semiconductor device can be formed in a short time since no epitaxial growth is employed.