摘要:
A field effect transistor has the property that the product of its series resistance and its true transconductance is less than one throughout the entire range of drain voltage in the operative state of the transistor, the series resistance being the sum of the resistance from source to channel and the resistance of this channel. In order to prevent an excessive increase in the active resistance of the channel, the channel is made to have an impurity concentration as low as less than 10.sup.15 atoms/cm.sup.3, preferably less than 10.sup.14 atoms/cm.sup.3, so that the depletion layers extending from the gates grow extensively to become contiguous in response to a small increase in the reverse gate voltage applied. As a result, the field effect transistor of this invention has an unsaturated drain current versus drain voltage characteristic.
摘要:
In a method of and an apparatus for epitaxially growing a chemical-compound crystal, a plurality of raw-material gasses are alternately introduced into a closed chamber of a crystal growing device to grow the crystal placed within the closed chamber. At growing of the crystal, a light from a light source is emitted to a crystal growing film of the crystal. Intensity of a light reflected from the crystal growing film and received by a photo detector is measured. Charge amounts of the respective raw-material gasses are controlled by a control system on the basis of a change in the reflected-light intensity, thereby controlling a growing rate of the growing film.
摘要:
A semiconductor device having a source region, a drain region and a channel region which are formed in a surface portion of a semiconductor substrate, and a gate formed with a material having a relatively high built-in voltage relative to the source region. This semiconductor device may further include, in the semiconductor substrate to extend along the channel region, a highly-doped region having a conductivity type opposite to that of the source region. This highly-closed region may have an impurity concentration gradient which is greater toward its portion facing the abovesaid surface of the substrate. These arrangements serve to prevent extinction of memory due to current leakage during absence of bias voltage which otherwise would develop in semiconductor devices having short-channel and thin gate oxide layer, and due to irradiation of alpha-particle onto the device.
摘要:
A semiconductor device comprises a semiconductive substrate of a low impurity concentration, a channel area of a low impurity concentration formed on the substrate, a source area formed on the channel area and having a high impurity concentration of a conductive type opposite to that of the substrate, a drain area formed on the channel area and having a high impurity concentration of a conductive type opposite to that of the substrate, and an accumulating gate area formed on the channel area and having a conductive type same as that of the substrate. The source area and drain area are arranged in a predetermined direction along the substrate. The accumulating gate area comprises a first part sandwiched between the source area and the drain area and extended in a direction crossing the predetermined direction and second and third parts connected with the first part and approximately extended in the predetermined direction. The accumulating gate area is adapted to accumulate a charge corresponding to the intensity of the incident radiation. A current flows from one to the other of the source area and the drain area through a part of the channel area sandwiched between the first part of the accumulating gate area and the substrate. The potential of the accumulating gate area varies according to the accumulated charge. The current varies according to the potential of the accumulating gate area.
摘要:
This invention provides a step cut type insulated gate static induction tsistor having a first main electrode formed in one major surface of a semiconductor substrate, a second main electrode formed in a bottom portion of a U-shaped groove formed in one major surface of a semiconductor substrate, a control electrode formed on a side wall of the U-shaped groove and consisting of a thin insulating film and a polysilicon layer, and a low-resistance electrode of a refractory metal layer or a refractory metal silicide layer formed in at least part of the side wall of the polysilicon layer of the control electrode.
摘要:
A thyristor device comprising an SI (Static induction) thyristor or beam base thyristor and an SIT (static induction transistor) or SIT-mode bipolar transistor connected to the gate of the thyristor in order to make it possible to turn-on and-off a direct current and voltage at a high speed with a light. In the thyristor part, the SIT gate structure or SIT-mode beam base structure exists in the first gate or base region or second gate or base region so that, at the time of the triggering operation, a very high switching efficiency will be obtained.
摘要:
An insulated-gate static induction transistor is formed by establishing a potential barrier in a semiconductor region of one conductivity type between the source and the drain regions of the other conductivity type. The height of the potential barrier should be sensitive to the drain voltage as well as to the gate voltage. Therefore, the semiconductor region should have a low impurity concentration and short length. The potential barrier can be established by varying the field effect of the gate voltage in the semiconductor region and/or by the built-in potential between the source region and the semiconductor region.
摘要:
A semiconductor thyristor of the Static Induction type having a split-gate structure, e.g., driving gates and non-driving gates, for controlling cathode-anode current flow. The split-gate structure comprises a plurality of primary gates formed in recesses of the channel region which respond to an external control signal for providing primary current control, and a plurality of secondary non-driving gates which are influenced by electric fields in the channel region extant during thyristor operation for providing secondary current control. In operation, the driving and non-driving gates coact so that the non-driving gates, having an induced potential lower than the potential applied to the driving gates, absorb charge carriers injected in the channel during thyristor operation. The relative disposition of the non-driving gates and the anode, as well as the respective doping concentrations of the anode and channel regions, enable the non-driving gates to absorb a substantial portion of charge carriers injected from the anode into the channel during high-power operation. Fast turn-on and turn-off is achieved by exclusion of the non-driving gate capacitance in the driving gate circuit.
摘要:
A pair of static induction thyristors, which are coupled in parallel in the opposite bias directions between an AC power source and a load, is turned on by a light signal and is turned off by natural commutation, a light signal or an electric signal. The turn-off light signal is generated within a phase angle of 90.degree. in the time axis around the zero-cross point of the AC voltage from the AC power source.
摘要:
An insulated-gate type transistor having a semi-conductor body of a low impurity concentration, a heavily-doped source region of a conductivity type opposite to that of the semiconductor body for supplying charge carriers, a heavily-doped drain region for receiving the carriers supplied from the source region, both of which regions may be provided separately in a main surface of the body, a channel region located between the source and drain regions for the travel of these carriers, an insulated-gate structure inputted with a gate voltage for controlling the travel of those carriers, a semiconductor region formed in the neighborhood of the source region within the body and having a portion located below the source region and another portion extending beyond therefrom toward the drain region and serving to define the channel region and to increase the ratio of the amount of carriers reaching the drain region to the total amount of the carriers supplied from the source region. This transistor can be easily manufactured with a single substrate from that side of the main surface. This transistor is suitable for use in constructing integrated circuits and enables construction of complementary devices.