摘要:
In manufacturing a field effect transistor, a pattern which has a wider upper layer and a narrower lower layer is formed at a gate electrode position. Using the pattern as a mask, first and second impurity regions are formed on both the sides of a gate region by ion implantation. Subsequently, at least the lower layer is buried in a material, such as an organic high polymer material, having a selectivity in etching characteristics with respect to the pattern material. After removing the lower layer, an electrode material is embedded in the resulting hole so as to form a gate electrode.
摘要:
This specification discloses a self-aligned manufacturing method of a Schottky gate FET. This method comprises the steps: forming a gate metallic layer on a semiconductor substrate and a mask overhanged on the metallic layer; ion-implanting impurity ions into the semiconductor substrate using the mask to form a source/drain region; depositing an insulator on the gate metallic layer side surface and the other surface below the mask; directionally etching said deposited insulator using the mask to expose the source/drain region; depositing a source/drain electrode using the mask; and removing the mask.
摘要:
A collector lead-out portion and a base lead-out portion are formed so as to oppose to each other in such a manner that active regions including a collector, a base and an emitter are sandwiched therebetween. The collector lead-out portion and the base lead-out portion are formed by ion implantation or selective epitaxial growth. Thus, a planar type heterojunction bipolar transistor capable of a high density of integration is formed.
摘要:
Herein disclosed is a field effect transistor fabricating method comprising: the step of forming a surface portion of a semiconductor substrate with an impurity region for a channel; the step of forming a first material layer, which has a width substantially equal to that of a gate electrode, in such a position on said semiconductor substrate and is to be formed with said gate electrode, a second material layer, which has a width larger than that of said first material layer, above said first material layer, and source and drain regions by an ion implantation using said first and second material layers thus formed as a mask; the step of forming source and drain electrodes in contact with said source and drain regions; the step of forming a third material layer, which has a selectivity with said first material layer in its etched characteristics, on the semiconductor body thus far prepared by the foregoing steps; the step of forming at least an aperture by removing said first material layer in a state using said third material layer as a mask; and the step of forming said gate electrode in said aperture.
摘要:
A heat-assisted magnetic recording head includes a thin film magnetic transducer having a pair of yokes and generating a magnetic field in a magnetic gap between two magnetic poles at the ends of the pair of yokes, and a heater placed in the vicinity of the magnetic gap and generating heat with an electric current. A part of a magnetic recording medium in the vicinity of the magnetic gap is heated by the heater to reduce a magnetic-coercive of the part of the magnetic recording medium and the magnetic field generated by the thin film magnetic transducer is applied to the part of the magnetic recording medium.
摘要:
An optical head which implements high recording density of a recording medium and which is miniaturized in size and improved in data transfer rate, a disk apparatus, and a method for manufacturing the optical head are provided. A laser beam is emitted from a semiconductor laser, the laser beam is collimated by the collimator lens to a collimated beam and reflected by a mirror, condensed by an condense lens, and incident to an incident surface of a transparent condensing medium. The condensed beam which was incident to the incident surface is refracted by the incident surface, the refracted beam is condensed on a condense surface, a beam spot is formed on the condense surface, and a near field wave leaks from a small aperture. The near field wave leaked from the small aperture propagates in a recording layer of a recording. The beam is served for recording/reproduction on the recording layer.
摘要:
A semiconductor laser device having an active layer which is comprised of a quantum well layer formed of a mixed crystal material, and barrier layers provided on both sides of the quantum well layer in such a manner as to sandwich the same, is characterized in that Ge is thermally diffused in a portion of the active layer to disorder the quantum well layer and the barrier layers at that portion so as to form a non-light-emitting area with a low refractive index, while the quantum well layer and the barrier layers at a portion where Ge is not diffused is formed as a refractive index waveguide which is a light-emitting area.
摘要:
A semiconductor member has a structure wherein a first semiconductor layer is held between second and third semiconductor layers which have forbidden band widths greater than a forbidden band width of the first semiconductor layer, and wherein only the second semiconductor layer which is formed on a side of the first semiconductor layer close to a substrate is doped with impurities. The semiconductor member constructs the depletion type with the first and second semiconductor layers, and the enhancement type with the first and third semiconductor layers. A semiconductor device can be properly formed in the enhancement or depletion type by selectively connecting the semiconductor layers.
摘要:
A method for recording and reproducing information characterized in that an information train in which synchronizing signals are arrayed at equal time intervals between information signals is recorded in an information track on a recording medium which is wobbled in synchronism with the synchronizing signals and at a frequency integral times the frequency of the synchronizing signals, that the information train recorded in the information track is read out by read-out means, and that a position of the read-out means is controlled on the basis of the information train read out. The wobbling waveform is 90.degree. out of phase with a harmonic component of the synchronizing signals.
摘要:
The present invention provides a magnetooptic device, a magnetooptic head, and a magnetic disk drive each capable of performing optically assisted magnetic recording and each having a small size, improved recording density, and a higher transfer rate. In a magnetooptic device, a magnetic circuit including a magnetic gap and a thin film magnetic transducer having a coil portion are stacked on the surface of a semiconductor laser. By the arrangement, optically assisted magnetic recording can be performed, small size and light weight are achieved, and higher transfer rate can be implemented.