摘要:
A vertical metal oxide semiconductor field effect transistor has a trench substantially vertically formed in a major surface of a semiconductor substrate, a first conductive layer formed in a predetermined region including a side wall surface of the trench on a gate insulating film, lower and upper diffusion layers formed in the bottom of the trench and a surface layer of the semiconductor substrate, preferably a channel doped region formed in the semiconductor substrate between the upper and lower diffusion layers, and a second conductive layer formed in contact with the lower diffusion layer in the bottom of the trench and insulated from the first conductive layer so as to fill the trench. The first conductive layer serves as a gate electrode, and the diffusion layers serves as source/drain regions, respectively. A method of manufacturing the vertical MOSFET is also proposed.
摘要:
A semiconductor device has memory cells respectively located at intersections of bit and word lines arranged in a matrix form, each of the memory cells being constituted by a single insulated gate transistor and a single capacitor. One memory cell is formed in an element formation region defined by each of trenches arranged in a matrix form. The capacitor has an insulating film formed along part of a side wall surface of a trench formed in at least a direction of thickness of a semiconductor substrate and a conductive layer formed along the insulating film. The transistor has a gate insulating film adjacent to the capacitor and formed along a remaining portion of the side wall surface of the trench, a gate electrode formed along the gate insulating film, and a diffusion region formed in a major surface of the semiconductor substrate which is adjacent to the gate insulating film. The semicondcutor memory device further has an isolation region between two adjacent ones of the memory cells along two adjacent ones of the bit or word lines. A method of manufacturing the semiconductor is also proposed.
摘要:
A read-only memory has memory cells each with a vertical metal oxide semiconductor field effect transistor and a bit line. The vertical metal oxide semiconductor field effect transistor has a gate electrode serving as a word line, a source, a drain, and a vertical channel region between the source and drain constituted by first and second diffusion layers. The gate electrode is formed on a side wall of a trench, which has a pair of side walls substantially perpendicular to a major surface of a semiconductor substrate of a first conductivity type and an interconnecting bottom surface substantially perpendicular to the side wall surfaces. The first and second diffusion layers of a second conductivity type are formed in an upper portion of the semiconductor substrate and in a bottom of the trench, respectively. The bit lines are formed in a predetermined pattern. One of the first and second diffusion layers is connected to the bit line through a contact hole and the other of the first and second diffusion layers is used as a common current line. A method of manufacturing the read-only memory is also proposed.
摘要:
A vertical metal oxide semiconductor field effect transistor has a trench substantially vertically formed in a major surface of a semiconductor substrate, a first conductive layer formed in a predetermined region including a side wall surface of the trench on a gate insulating film, lower and upper diffusion layers formed in the bottom of the trench and a surface layer of the semiconductor substrate, preferably a channel doped region formed in the semiconductor substrate between the upper and lower diffusion layers, and a second conductive layer formed in contact with the lower diffusion layer in the bottom of the trench and insulated from the first conductive layer so as to fill the trench. The first conductive layer serves as a gate electrode, and the diffusion layers serves as source/drain regions, respectively. A method of manufacturing the vertical MOSFET is also proposed.
摘要:
A semiconductor memory device has a semiconductor substrate of one conductivity type in which a plurality of memory cells are formed, each of the plurality of memory cells including at least one capacitor and having a trench which is formed from one major surface of the semiconductor substrate so as to surround at least one memory cell, wherein a first insulating film having element isolation properties is formed on a bottom and most areas of side wall surfaces of the trench, a first conductive film serving as one electrode of the capacitor is formed on the side wall of the first insulating film and an exposed portion of the semiconductor substrate which is not covered with the first insulating film, a second insulating film is formed on the first conductive film, and a second conductive film serving as the other electrode of the capacitor is formed on the second insulating film.
摘要:
A semiconductor device with a metal-insulator-semiconductor capacitor has:a semiconductor substrate having a predetermined conductivity type and serving as one electrode of the metal-insulator-semiconductor capacitor, the semiconductor substrate being provided with a trench of a cross-sectionally rectangular shape which extends along a direction of thickness of the semiconductor substrate from a major surface thereof;a doped semiconductor layer formed along at least side wall surfaces of the trench, the semiconductor layer, which is formed by deposition and etching, being provided with an outer surface, starting to extend in a rounded shape from major surface portions of the semiconductor substrate and extending substantially parallel to the side wall surfaces of the trench, and a recess, which is defined by the semiconductor layer, having round corners at the bottom;a dielectric insulating layer formed on an exposed surface including the major surface of the semiconductor substrate and the outer surface of the semiconductor layer; anda conductive layer formed on the insulating layer to bury trench and serving as the other electrode.
摘要:
A pipelined AD converter (1) includes a plurality of conversion stages (11, 11, . . . ). In each of the conversion stages, an analog-to-digital conversion circuit (101) converts an input voltage (Vin) from the preceding stage to a digital code (Dout). A digital-to-analog conversion circuit (102) converts the digital code obtained by the analog-to-digital conversion circuit to an intermediate voltage (Vda). A charge operation circuit (103) has: a capacitor section (C1, C2) for sampling the input voltage; and an amplifier section (104) for amplifying a mixed voltage of the input voltage sampled by the capacitor section and the intermediate voltage obtained by the digital-to-analog conversion circuit. The amplifier section (104) includes a plurality of op-amps (amp1, amp1, . . . ) having the same configuration and connected in parallel with each other.
摘要:
A pipelined AD converter (1) includes a plurality of conversion stages (11, 11, . . . ). In each of the conversion stages, an analog-to-digital conversion circuit (101) converts an input voltage (Vin) from the preceding stage to a digital code (Dout). A digital-to-analog conversion circuit (102) converts the digital code obtained by the analog-to-digital conversion circuit to an intermediate voltage (Vda). A charge operation circuit (103) has: a capacitor section (C1, C2) for sampling the input voltage; and an amplifier section (104) for amplifying a mixed voltage of the input voltage sampled by the capacitor section and the intermediate voltage obtained by the digital-to-analog conversion circuit. The amplifier section (104) includes a plurality of op-amps (amp1, amp1, . . . ) having the same configuration and connected in parallel with each other.
摘要:
A current mirror circuit 10 is formed to have a current ratio (a transistor size ratio) of 1:m. As well, respective pairs of nMOS transistors MN1, MN3 and nMOS transistors MN2, MN4 are formed to have a current ratio of 1:m. Two currents output from the current mirror circuit 10 are each distributed to two. The distributed currents flowing in the nMOS transistors MN2, MN4 are added and are then allowed to flow into one resistor R2. Hence, for the resistor R2, only one resistor in which current of double flows suffices when m=1, for example. This effortlessly reduces the necessary resistance to one fourth.
摘要:
A high-level period of each of n first pulse signals partially or wholly overlaps a period during which all of n second pulse signals are at the low level. A high-level period of each of the n second pulse signals partially or wholly overlaps a period during which all of the n first pulse signals are at the low level. Each of n first drive transistors includes a source connected to a ground node, a drain connected to a first node, and a gate receiving a corresponding one of the first pulse signals. Each of n second drive transistors includes a source connected to the ground node, a drain connected to a second node, and a gate receiving a corresponding one of the second pulse signals. A current mirror circuit allows a current corresponding to a current flowing through the second node to flow through the first node.