Abstract: A method of manufacturing a semiconductor memory device having nonvolatile memory cells each formed of a MISFET having both a floating gate and a control gate and first and second semiconductor regions. By this method, an impurity, for example, arsenic, is introduced to form both the first and second semiconductor regions but, however, a lower dose of arsenic is introduced in the formation of the second semiconductor region. The first semiconductor region is formed to have a junction depth greater than that of the second semiconductor region, and both the first and second semiconductor regions have portions thereof extending under the floating gate electrode. Carriers stored in the floating gate electrode are transferred between the floating gate electrode and the first semiconductor region by tunneling through the insulating film beneath the floating gate electrode. The method further features the formation of MISFETs of peripheral circuits.

Abstract: An information retention capability based on a memory cell which comprises a pair of nonvolatile memory elements in a differential form is improved. A nonvolatile memory element (130) constituting a flash memory is so constructed that its tunnel oxide film (GO3) and floating gate electrode (FGT) are respectively formed by utilizing the gate oxide film (GT2) and gate electrode (GT2) of a transistor for a circuit which is formed on the same semiconductor substrate as that of the element (130). A memory cell is constructed in a 2-cells/1-bit scheme in which a pair of nonvolatile memory elements can be respectively connected to a pair of complementary data lines, and threshold voltage states different from each other are set for the nonvolatile memory elements so as to differentially read out data.

Abstract: An information retention capability based on a memory cell which comprises a pair of nonvolatile memory elements in a differential form is improved. A nonvolatile memory element (130) constituting a flash memory is so constructed that its tunnel oxide film (GO3) and floating gate electrode (FGT) are respectively formed by utilizing the gate oxide film (GT2) and gate electrode (GT2) of a transistor for a circuit which is formed on the same semiconductor substrate as that of the element (130). A memory cell is constructed in a 2-cells/1-bit scheme in which a pair of nonvolatile memory elements can be respectively connected to a pair of complementary data lines, and threshold voltage states different from each other are set for the nonvolatile memory elements so as to differentially read out data.

Abstract: A method of manufacturing a semiconductor memory device having nonvolatile memory cells each formed of a MISFET having both a floating gate and a control gate and first and second semiconductor regions. By this method, an impurity, for example, arsenic, is introduced to form both the first and second semiconductor regions but, however, a lower dose of arsenic is introduced in the formation of the second semiconductor region. The first semiconductor region is formed to have a junction depth greater than that of the second semiconductor region, and both the first and second semiconductor regions have portions thereof extending under the floating gate electrode. Carriers stored in the floating gate electrode are transferred between the floating gate electrode and the first semiconductor region by tunneling through the insulating film beneath the floating gate electrode. The method further features the formation of MISFETs of peripheral circuits.

Abstract: A gate electrode of each MISFET is formed on a substrate in an active region whose periphery is defined by an element isolation trench, and crosses the active region so as to extend from one end thereof to the other end thereof. The gate electrode has a gate length in a boundary region defined between the active region and the element isolation trench, which gate length is greater than a gate length in a central portion of the active region. The gate electrode is configured in an H-type flat pattern as a whole. Further, the gate electrode covers the whole of one side extending along a gate-length direction, of the boundary region defined between the active region L and the element isolation trench, and parts of two sides thereof extending along a gate-width direction. The MISFETs are respectively formed in electrically separated wells and are connected in series so as to constitute part of a reference voltage generating circuit.

Abstract: A semiconductor memory device having nonvolatile memory cells of a single-element type. The nonvolatile memory cells have a floating gate electrode insulatedly on a main surface of a semiconductor substrate and a control gate electrode on the floating gate via a second gate insulating film. An impurity, for example, arsenic, is introduced in self-alignment with the pair of opposing end sides of the control gate electrode to form both the first and second semiconductor regions but, however, a lower dose of arsenic is introduced in the formation of the second semiconductor region. In accordance with the scheme, the first semiconductor region is formed to have a junction depth greater than the junction depth associated with the second semiconductor region and both the first and second semiconductor regions have portions thereof extending under the floating gate electrode.

Abstract: A device capable of obtaining an electromagnetic wave having an arbitrary waveform and an arbitrary frequency, generating an electromagnetic wave with an ultrahigh frequency, generating an electromagnetic wave with a variable frequency, and performing ultrafast optical control and optical modulation is provided. The quantum synthesizer of the present invention has a quantum synthesis portion comprising a number, n (n=an integer of 3 or more), of quantum wells provided in proximity to each other so as to be coupled together quantum-mechanically, each of the n number of quantum wells having the n number or number larger than n of coupled levels as a result of coupling, and is adapted to excite and synthesize the electron waves or polarizations of the respective levels, while controlling their phases and amplitudes, by means of coded light with phases and amplitudes controlled for predetermined frequencies (energies).

Abstract: A method of manufacturing a semiconductor memory device having nonvolatile memory cells of a single-element type. The method provides for the formation of a floating gate electrode insulatedly on a main surface of a semiconductor substrate and a control gate electrode on the floating gate via a second gate insulating film. Also by this method, an impurity, for example, arsenic, is introduced in self-alignment with the pair of opposing end sides of the control gate electrode to form both the first and second semiconductor regions but, however, a lower dose of arsenic is introduced in the formation of the second semiconductor region. In accordance with the scheme, the first semiconductor region is formed to have a junction depth greater than the junction depth associated with the second semiconductor region and both the first and second semiconductor regions have portions thereof extending under the floating gate electrode.

Abstract: A method for fabricating a semiconductor integrated circuit device comprising a nonvolatile memory cell, comprises the steps of forming a first gate material which comprises a silicon film containing no impurities, whose top surface is covered with an oxidation-resistant mask, and whose width in the gate-length direction is prescribed, on part of the surface of a first gate insulating film, forming a thermal-oxidation insulating film on the surface of an active region of a semiconductor substrate through thermal oxidation, removing an oxidation-resistant mask, forming a second gate material which comprises a silicon film into which impurities are introduced and whose width in the gate-length direction is prescribed, on each surface of the thermal-oxidation insulating film and the first gate material forming a second gate insulating film on the surface of the second gate material, and forming a third gate material on the surface of the second gate insulating film.

Abstract: A method of manufacturing a semiconductor memory device having non-volatile memory elements or memory cells of a single-element type. The method provides for the formation of a floating gate electrode on a main surface of a semiconductor substrate and a control gate electrode on the floating gate electrode via a second gate insulating film. In accordance with the method, an impurity is introduced in self-alignment with one of a pair of opposing end portions of the control gate electrode to form a first semiconductor region, and on the second of the opposing end portions of the control gate electrode of the memory cell, the same impurity, for example, arsenic, but, however, of a lower dose is introduced in self-alignment to form a second semiconductor region.

Abstract: A semiconductor integrated device having a non-volatile memory element or memory cell of a single-element type in a non-volatile memory circuit employing a field effect transistor which has, in addition to a floating gate electrode for storage of information and a controlling gate electrode, a source which includes a heavily doped region having a depth into the semiconductor substrate extending from the major surface thereof which is large. The single-element type field effect transistor, furthermore, has a drain which includes a lightly doped region which has a depth extending into the semiconductor substrate from the major surface thereof which is small.

Abstract: A semiconductor integrated device having a non-volatile memory element or memory cell of a single-element type in a non-volatile memory circuit employing a field effect transistor which has, in addition to a floating gate electrode for storage of information and a controlling gate electrode, a source which includes a heavily doped region having a depth into the semiconductor substrate extending from the major surface thereof which is large. The single-element type field effect transistor, furthermore, has a drain which includes a lightly doped region which has a depth extending into the semiconductor substrate from the major surface thereof which is small.

Abstract: This invention discloses EEPROM which increases an erasing voltage V.sub.pp to be applied in a data write cycle by increasing an avalanche breakdown voltage between a source region and a semiconductor substrate in order to improve erasing efficiency, and employs a structure which strengthens the electric field at the edge of a drain region in order to let hot carrier be easily generated and to improve writing efficiency.

Abstract: An EEPROM (Electrically Erasable Programmable Read Only Memory) has a structure in which the corners of a floating gate electrode of each memory cell MISFET near the source region thereof are rounded.The EEPROM is manufactured by a method characterized in that the ions of an impurity at a high dose are implanted in self-alignment with the floating gate electrode and control gate electrode of the memory cell MISFET so as to form the source and drain regions thereof, whereupon an oxidizing treatment is carried out.

Abstract: This invention discloses EEPROM which increases an erasing voltage V.sub.pp to be applied in a data write cycle by increasing an avalanche breakdown voltage between a source region and a semiconductor substrate in order to improve erasing efficiency, and employs a structure which strengthens the electric field at the edge of a drain region in order to let hot carrier be easily generated and to improve writing efficiency.

Abstract: An EEPROM (Electrically Erasable Programmable Read Only Memory) has a structure in which the corners of a floating gate electrode of each memory cell MISFET near the source region thereof are rounded.The EEPROM is manufactured by a method characterized in that the ions of an impurity at a high dose are implanted in self-alignment with the floating gate electrode and control gate electrode of the memory cell MISFET so as to form the source and drain regions thereof, whereupon an oxidizing treatment is carried out.

Abstract: Herein disclosed is a semiconductor integrated circuit device having a nonvolatile memory function and including a memory cell composed of a field effect transistor having a floating gate electrode and a control gate electrode. A first insulating film for element isolation is buried between the floating gate electrodes. The size of the drain region of the field effect transistor is substantially regulated by both the gap between the first insulating films adjacent to the drain region and the gap between the control gate electrodes adjacent to the drain region. The gaps between the data line at the connection portion with the drain region and the first insulating films individually adjacent to the drain region are equalized. The gaps between the data line at the connection portion with the drain region and the floating gate electrodes or control gate electrodes individually adjacent to the drain region are equalized.

Abstract: A semiconductor integrated device having a non-volatile memory element or memory cell of a single-element type in a non-volatile memory circuit employing a field effect transistor which has, in addition to a floating gate electrode for storage of information and a controlling gate electrode, a source which includes a heavily doped region having a depth into the semiconductor substrate extending from the major surface thereof which is large. The single-element type field effect transistor, furthermore, has a drain which includes a lightly doped region which has a depth extending into the semiconductor substrate from the major surface thereof which is small.

Abstract: Disclosed is a semiconductor integrated circuit device which includes first field effect transistors of an LDD structure having a floating gate as memory cells and second field effect transistors of the LDD structure as elements other than the memory cells, and which is used as EPROM. A shallow, low impurity concentration region of the first field effect transistor as a part of its source or drain region has a higher impurity concentration than a shallow, low impurity concentration region of the second field effect transistor as a part of its source or drain region.

Abstract: This invention discloses EEPROM which increases an erasing voltage V.sub.pp to be applied in a data write cycle by increasing an avalanche breakdown voltage between a source region and a semiconductor substrate in order to improve erasing efficiency, and employs a structure which strengthens the electric field at the edge of a drain region in order to let hot carrier be easily generated and to improve writing efficiency.