Abstract: Provided are a semiconductor device that can obtain more output current without increasing the occupied area of a MOS transistor, and a method for manufacturing the same. MOS transistors (M11, M12) are electrically isolated by a trench isolation oxide film (21). The MOS transistor (M11) has a groove portion (GP) in which the width of the top is 20 nm to 80 nm and the depth is 50 nm to 150 nm. The groove portion (GP) is disposed at the boundary part between a trench isolation insulating film (22) and an active region (AR1) so as to surround the active region (AR1). A gate electrode (31A) is not only disposed above the active region (AR1) but also buried in the groove (GP) with a gate oxide film (30) interposed therebetween.

Abstract: The semiconductor device has a triple well structure. The triple well and other wells have impurity concentration distributions in the depth direction, which are determined in accordance with required function. Thereby, the required performances such as suppression of a leak current can be achieved even in a miniaturized structure.

Abstract: A nonvolatile semiconductor memory device includes an n-type region which is in contact with n+ drain diffusion region at a surface of p-type silicon substrate and covers the periphery thereof. The device also includes a p-type impurity region which is in contact with n-type region and covers the periphery thereof. The n+ drain diffusion region, n-type region and p+ impurity region extend to region located immediately under the floating gate electrode. Thereby, the nonvolatile semiconductor memory device has a structure which can promote injection of high energy electrons along a gate electrode direction.

Abstract: P wells (11, 12) having different impurity profiles are adjacently formed in a surface (50S) of a semiconductor substrate (50). A P-type layer (20) having lower resistivity than the P wells (11, 12) is formed in the surface (50S) across the P wells (11, 12), so that the P wells (11, 12) are electrically connected with each other through the P-type layer (20). Contacts (31, 32) fill in contact holes (70H1, 70H2) formed in an interlayer isolation film (70) respectively in contact with the P-type layer (20). The contacts (31, 32) are connected to a wire (40). The wire (70) is connected to a prescribed potential, thereby fixing the P wells (11, 12) to prescribed potentials through the contacts (31, 32) and the P-type layer (20). Thus, the potentials of the wells can be stably fixed and the layout area of elements for fixing the aforementioned potentials can be reduced.

Abstract: Provided are a semiconductor device that can obtain more output current without increasing the occupied area of a MOS transistor, and a method for manufacturing the same. MOS transistors (M11, M12) are electrically isolated by a trench isolation oxide film (21). The MOS transistor (M11) has a groove portion (GP) in which the width of the top is 20 nm to 80 nm and the depth is 50 nm to 150 nm. The groove portion (GP) is disposed at the boundary part between a trench isolation insulating film (22) and an active region (AR1) so as to surround the active region (AR1). A gate electrode (31A) is not only disposed above the active region (AR1) but also buried in the groove (GP) with a gate oxide film (30) interposed therebetween.

Abstract: A semiconductor device and manufacturing method are provided in which an increase in contact resistance between a plug and a semiconductor layer and an increase in junction leakage current in a semiconductor layer to which a plug is connected can be prevented and fabrication cost and device area can be reduced. A multi-layer film comprising a metal layer (45), a barrier metal layer (44), a polysilicon layer (43), and a barrier metal layer (42) is patterned by photolithography and etching to form poly-metal bit lines (160) electrically connected to buried layers (43A, 43B) and polysilicon plugs (29).

Abstract: An object is to prevent protrusion of a plug from an interlayer insulating film to prevent formation of a step between circuit parts exceeding a step height allowed in a planarization process and also to prevent formation of particles due to a protruded plug. An interlayer insulating film (11) is etched back over the entire surface under an etching condition in which the etching selectivity of a polysilicon plug (13) with respect to the interlayer insulating film (11) is 10, for example, to recess the polysilicon plug (13) to a given depth in a bit line contact hole (12) to form a recessed polysilicon plug (27).

Abstract: A semiconductor device and manufacturing method are provided in which an increase in contact resistance between a plug and a semiconductor layer and an increase in junction leakage current in a semiconductor layer to which a plug is connected can be prevented and fabrication cost and device area can be reduced. A multi-layer film comprising a metal layer (45), a barrier metal layer (44), a polysilicon layer (43), and a barrier metal layer (42) is patterned by photolithography and etching to form poly-metal bit lines (160) electrically connected to buried layers (43A, 43B) and polysilicon plugs (29).

Abstract: A nonvolatile semiconductor memory device includes an n-type region which is in contact with n+ drain diffusion region at a surface of p-type silicon substrate and covers the periphery thereof. The device also includes a p-type impurity region which is in contact with n-type region and covers the periphery thereof. The n+ drain diffusion region, n-type region and p+ impurity region extend to region located immediately under the floating gate electrode. Thereby, the nonvolatile semiconductor memory device has a structure which can promote injection of high energy electrons along a gate electrode direction.

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: Provided are a semiconductor device which can prevent occurrence of inconvenience caused by overetching resulting from difference between depths of contact holes simultaneously formed in a memory cell part and a peripheral circuit part and inconvenience resulting from extreme increase of an aspect ratio of the contact holes, and a method of fabricating the same. An aluminum wire (22) provided on an interlayer insulating film (20) of a peripheral circuit part is electrically connected with semiconductor diffusion regions, i.e., N.sup.+ -type source/drain regions (91, 92) (first semiconductor regions) and P.sup.+ -type source/drain regions (81, 82) (second semiconductor regions) by a bit line contact hole (12) formed through the interlayer insulating film (11) to have a buried layer (25) therein and an aluminum wire contact hole (21B) formed through other interlayer insulating films (14, 20) to have a buried layer (27) therein.

Abstract: In a semiconductor device, a plurality of MIS transistors of the same conductivity type having different thresholds are formed at a main surface of semiconductor substrate, and impurity profiles on section extending in a depth direction from the main surface of the semiconductor substrate through respective channel regions of the plurality of MIS transistors have peaks located at different depths. This structure is formed by ion implantation performed on the respective channel regions with different implanting energies or different ion species. According to this semiconductor device, the thresholds of the MIS transistors can be individually controlled, and transistor characteristics optimum for uses can be obtained.

Abstract: With a semiconductor device and according to a manufacturing method of the invention, a trade-off relationship between a threshold value and a diffusion layer leak is eliminated, and it is not necessary to form a gate oxide film at a plurality of steps. Gate electrodes (4A, 4B and 4C) respectively comprise a polysilicon layer (M1) and a WSi layer (L1), the polysilicon layer (M1) and a WSi layer (L2), the polysilicon layer (M1) and a WSi layer (L3), which are respectively stacked in this order on a gate oxide film (3). Channel dope layers (103A, 103B and 103C) are formed within a well layer (101) respectively under the gate electrodes (4A, 4B and 4C).

Abstract: In a semiconductor device and a method of manufacturing the same according to the present invention, a trade-off relationship between threshold values and a diffusion layer leakage is eliminated and it is not necessary to form gate oxide films at more than one stages. Since doses of nitrogen are different from each other between gate electrodes (4A to 4C) of N-channel type MOS transistors (T41 to T43), concentrations of nitrogen in the nitrogen-introduced regions (N1 to N3) are accordingly different from each other. Concentrations of nitrogen in the gate electrodes are progressively lower in the order of expected higher threshold values.

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: An n well and a p well are formed in a silicon substrate. The n well has n type impurity concentration peaks and a p type impurity concentration peak. The p well has p type concentration peaks. The impurity concentration peaks serving as channel stopper regions for isolating elements exist only in proximity to the lower surface of an isolation oxide film but not in element regions.

Abstract: An electrode wiring layer of a semiconductor device according to this invention includes a first conductive portion formed of polycrystalline silicon or the like, and second conductive portions formed as refractory metal silicide layers on opposite lateral walls of the first conductive portion. Upper surfaces and lateral surfaces thereof are coated with insulating layers formed in separate processes. The insulating layers covering the lateral surfaces in particular are formed by a self-aligning technique requiring no mask process. Where conductive layers are formed over the wiring layer according to this invention, a film forming and patterning process for insulating the conductive portions of the wiring layer is omitted and insulation of the wiring layer is secured.

Abstract: A semiconductor device includes a p-type semiconductor layer, a punch-through stopper layer having a positive impurity concentration and formed on an upper side of the p-type semiconductor layer, a buried layer formed on an upper surface of the punch-through stopper layer in a channel region, N-type source and drain regions of an LDD construction sandwiching the buried layer therebetween, a gate oxide film formed on the buried layer, and a gate electrode opposed to the buried layer, with a gate oxide film therebetween, wherein the punch-through stopper layer is shallower than the drain region.

Abstract: Disclosed is a MOSFET for controlling the flow of a large number of carriers from one source/drain region to the other source/drain region by applying a voltage to a gate. This MOSFET includes a semiconductor substrate and a transistor. The transistor includes a gate provided on the semiconductor substrate, one source/drain region and the other source/drain region both having a first conductivity type. The MOSFET includes first and second wells of a second conductivity type formed apart from each other on opposite sides of the gate in the main surface of the semiconductor substrate. The first well is such a small well as to accommodate only one source/drain region, while the second well is such a small well as to accommodate only the other source/drain region. The one source/drain region and the other source region are formed in the first and second wells, respectively. No distortion due to thermal stresses remains in the resultant MOSFET, and consequently a highly reliable MOSFET is obtained.

Abstract: An electrode wiring layer of a semiconductor device according to this invention includes a first conductive portion formed of polycrystalline silicon or the like, and second conductive portions formed as refractory metal silicide layers on opposite lateral walls of the first conductive portion. Upper surfaces and lateral surfaces thereof are coated with insulating layers formed in separate processes. The insulating layers covering the lateral surfaces in particular are formed by a self-aligning technique requiring no mask process. Where conductive layers are formed over the wiring layer according to this invention, a film forming and patterning process for insulating the conductive portions of the wiring layer is omitted and insulation of the wiring layer is secured.