Abstract: The invention is intended to shorten a positioning time required for forming an irradiation area with high accuracy using a number of leaf plates, and to reduce physical and mental burdens imposed on patients. A multi-leaf collimator comprises leaf plate driving body each including a plurality of movable leaf plates and provided respectively on one side and the other side, the plurality of leaf plates of the leaf plate driver on one side and the plurality of leaf plates of the leaf plate driver on the other side being disposed in an opposing relation to form an irradiation field of a radiation beam between the opposing leaf plates. Each of the leaf plate driving body includes a motor provided in common to the plurality of leaf plates. Driving force of the motor can be transmitted to the plurality of leaf plates at the same time through a pinion gear, upper and lower air cylinders, and upper and lower guides. Also, the driving force can be cut off selectively for each leaf plate.

Abstract: The invention is intended to shorten a positioning time required for forming an irradiation area with high accuracy using a number of leaf plates, and to reduce physical and mental burdens imposed on patients. A multi-leaf collimator comprises leaf plate driving body each including a plurality of movable leaf plates and provided respectively on one side and the other side, the plurality of leaf plates of the leaf plate driver on one side and the plurality of leaf plates of the leaf plate driver on the other side being disposed in an opposing relation to form an irradiation field of a radiation beam between the opposing leaf plates. Each of the leaf plate driving body includes a motor provided in common to the plurality of leaf plates. Driving force of the motor can be transmitted to the plurality of leaf plates at the same time through a pinion gear, upper and lower air cylinders, and upper and lower guides. Also, the driving force can be cut off selectively for each leaf plate.

Abstract: The present invention provides an increased degree of uniformity of radiation dose distribution for the interior of a diseased part. A particle beam therapy system includes a charged particle beam generation apparatus and an irradiation apparatus. An ion beam is generated by the charged particle beam generation apparatus. The irradiation apparatus exposes a diseased part to the generated ion beam. A scattering device, a range adjustment device, and a Bragg peak spreading device are installed upstream of a first scanning magnet and a second scanning magnet. The scattering device and the range adjustment device are combined together and moved along a beam axis, whereas the Bragg peak spreading device is moved independently along the beam axis. The scattering device moves to adjust the degree of ion beam scattering. The range adjustment device moves to adjust ion beam scatter changes caused by an absorber thickness adjustment.

Abstract: This invention provides a hetero-junction bipolar transistor (HBT) having a large base-collector breakdown voltage. The HBT has a collector, a base and an emitter. The emitter is made of a semiconductor material whose band gap energy is greater than that of the base. An passivation layer made of a semiconductor material cover the collector, the base and the emitter and the band gap energy of the passivation layer is greater than that of the collector and the base.

Abstract: The present invention provides an increased degree of uniformity of radiation dose distribution for the interior of a diseased part. A particle beam therapy system includes a charged particle beam generation apparatus and an irradiation apparatus. An ion beam is generated by the charged particle beam generation apparatus. The irradiation apparatus exposes a diseased part to the generated ion beam. A scattering device, a range adjustment device, and a Bragg peak spreading device are installed upstream of a first scanning magnet and a second scanning magnet. The scattering device and the range adjustment device are combined together and moved along a beam axis, whereas the Bragg peak spreading device is moved independently along the beam axis. The scattering device moves to adjust the degree of ion beam scattering. The range adjustment device moves to adjust ion beam scatter changes caused by an absorber thickness adjustment.

Abstract: This invention provides a new configuration and manufacturing method of the hetero-junction bipolar transistor. According to the invention, the HBT comprises a semi-insulating InP substrate, a buffer layer on the substrate, a sub-collector layer, a collector layer, a base layer, an emitter layer, and an emitter contact layer These layers are sequentially grown on the buffer layer. Since a pre-processing of forming two depressions in the sub-collector layer before growing the collector layer, the top surface of the emitter layer becomes planar surface. This results on the reduction of pits induced in the etching of the emitter contact layer, thus enhances the reliability and the high frequency performance of the HBT.

Abstract: A hetero-bipolar transistor according to the present invention enhances reliability that relates to the breaking of wiring metal. The transistor comprises a semiconductor substrate, a sub-collector layer formed on a (100) surface of the substrate, a collector mesa formed on the sub-collector layer, and an emitter contact layer. The transistor further includes a collector electrode and wiring metal connected to the collector electrode. The edge of the sub-collector layer forms a step S, the angle of which is in obtuse relative to the substrate. Therefore, the wiring metal traversing the step S bends in obtuse angle at the step S, thus reducing the breaking of the wiring metal.

Abstract: A medical charged particle irradiation apparatus capable of irradiation from upward and horizontal directions and performing a preparing/ascertaining work without any separate device such as a moving capsule or the like comprising a patient's bed, on which a patient lies, a transport equipment for injecting and transporting charged particle beams toward the patient's bed, an irradiation field forming device for forming an irradiation field for the beams transported by the transport equipment, and a gantry provided to be rotatable about an axis of rotation, and wherein the irradiation field forming device is eccentrically arranged such that an axis of irradiation passes a position different from the axis of rotation, and the patient's bed is arranged on an opposite side of the transport equipment to a plane, which contains the axis of rotation and is substantially perpendicular to the axis of irradiation.

Abstract: The present invention provides a Hetero-Bipolar Transistor that suppresses a recombination current between electrons in the conduction band of an emitter and holes in the valence band of a base, which results on an enhancement of the current gain of the transistor. The HBT according to the present invention comprises a semi-insulating semiconductor substrate and a series of semiconductor layers on the substrate. The semiconductor layers are a buffer layer, a sub-collector layer a collector layer, a base layer, an emitter layer, an emitter contact layer, and an intermediate layer between the emitter layer and the emitter contact layer. The emitter layer has a carrier concentation of 1.0×1019 cm−3.

Abstract: The present invention relates to a PIN photo diode, whish shows both high sensitivity and superior high frequency performance by the reduction of the dark current and the intrinsic capacitance. The PIN diode comprises a substrate made of InP, n-type layer made of InGaAs doped with Si, i-type layer made of GaInAs with unintentionally doped, and the p-type layer made of GaInAs doped with Zn, respective layers are sequentially grown and formed to a mesa structure by conventional technique. A passivation layer of InP covers the p-type layer and the i-type layer. The thickness h2 of a center region of the p-type layer is thinner than the thickness h1 of other region surrounding the center. By the configuration, the reduction of the dark current, the enhancing of the high frequency performance by the reduction of the intrinsic capacitance, and the improvement of the sensitivity by the decreasing the absorption in the p-type layer are achieved.

Abstract: This invention provides a new configuration and manufacturing method of the hetero-junction bipolar transistor. According to the invention, the HBT comprises a semi-insulating InP substrate, a buffer layer on the substrate, a sub-collector layer, a collector layer, a base layer, an emitter layer, and an emitter contact layer These layers are sequentially grown on the buffer layer. Since a pre-processing of forming two depressions in the sub-collector layer before growing the collector layer, the top surface of the emitter layer becomes planar surface. This results on the reduction of pits induced in the etching of the emitter contact layer, thus enhances the reliability and the high frequency performance of the HBT.

Abstract: The present invention relates to a hetero-bipolar transistor. This transistor comprises a semi-insulating InP substrate, a buffer layer on the substrate, a sub-collector layer on the buffer layer, a collector layer on the sub-collector layer, a base layer on the collector layer, a wide-gap emitter layer on the base layer and a emitter contact layer on the emitter layer. The emitter layer extends the emitter contact layer, so the edge of the emitter layer is apart from the emitter contact layer and entirely covers the region where the collector layer and the sub-collector layer are overlapped to each other. According to this configuration, the transistor shows the enhanced reliability and the improved high frequency performance.

Abstract: The present invention relates to a PIN photo diode, whish shows both high sensitivity and superior high frequency performance by the reduction of the dark current and the intrinsic capacitance. The PIN diode comprises a substrate made of InP, n-type layer made of InGaAs doped with Si, i-type layer made of GaInAs with unintentionally doped, and the p-type layer made of GaInAs doped with Zn, respective layers are sequentially grown and formed to a mesa structure by conventional technique. A passivation layer of InP covers the p-type layer and the i-type layer. The thickness h2 of a center region of the p-type layer is thinner than the thickness h1 of other region surrounding the center. By the configuration, the reduction of the dark current, the enhancing of the high frequency performance by the reduction of the intrinsic capacitance, and the improvement of the sensitivity by the decreasing the absorption in the p-type layer are achieved.

Abstract: The present invention relates to a hetero-bipolar transistor. This transistor comprises a semi-insulating InP substrate, a buffer layer on the substrate, a sub-collector layer on the buffer layer, a collector layer on the sub-collector layer, a base layer on the collector layer, a wide-gap emitter layer on the base layer and a emitter contact layer on the emitter layer. The emitter layer extends the emitter contact layer, so the edge of the emitter layer is apart from the emitter contact layer and entirely covers the region where the collector layer and the sub-collector layer are overlapped to each other. According to this configuration, the transistor shows the enhanced reliability and the improved high frequency performance.

Abstract: A method of making a heterojunction bipolar transistor comprises the steps of: forming a mask layer on a compound semiconductor film by using a photomask for forming an emitter; and forming the emitter by wet-etching the compound semiconductor film by using the mask layer. The photomask has a pattern thereon for forming the emitter. The pattern is defined by a first area R associated with the shape of the emitter to be formed, and a plurality of second areas T1 to T4. Each of the second areas T1 to T4 includes first and second sides S1 and S2 meeting each other to form an acute angle therebetween, and a third side S3 in contact with the first area R. In each of the second areas T1 to T4, one side S3 of the two sides meeting each other to form a right angle therebetween is in contact with one side of the area R, whereas the other side S1 is connected to another side of the first area R to form a line segment.

Abstract: The invention is intended to shorten a positioning time required for forming an irradiation area with high accuracy using a number of leaf plates, and to reduce physical and mental burdens imposed on patients. A multi-leaf collimator comprises leaf plate driving body each including a plurality of movable leaf plates and provided respectively on one side and the other side, the plurality of leaf plates of the leaf plate driver on one side and the plurality of leaf plates of the leaf plate driver on the other side being disposed in an opposing relation to form an irradiation field of a radiation beam between the opposing leaf plates. Each of the leaf plate driving body includes a motor provided in common to the plurality of leaf plates. Driving force of the motor can be transmitted to the plurality of leaf plates at the same time through a pinion gear, upper and lower air cylinders, and upper and lower guides. Also, the driving force can be cut off selectively for each leaf plate.

Abstract: A liquid crystal device of this invention is constituted by a display cell, a compensation cell, and a pair of polarizing plates. The display cell is designed such that electrodes are respectively formed on the opposing surfaces of a pair of substrates, arranged to oppose each other through a predetermined gap, to be perpendicular to each other, alignment films are respectively formed to cover the electrodes, and a first liquid crystal material is sealed between the substrates to be twisted at a predetermined angle. The compensation cell is arranged to be stacked on the display cell. The compensation cell is designed such that a second liquid crystal material is sealed between a pair of substrates, subjected to alignment processing, to be twist-aligned in a direction opposite to the twist direction of the first liquid crystal material. The pair of polarizing plates are arranged to sandwich the display and compensation cells. A refractive index anisotropy .DELTA.n.sub.

Abstract: A liquid crystal display device includes a pair of substrates opposed to each other, a plurality of first electrodes provided on one of the paired substrates, a plurality of second electrodes mounted over the other base plate to oppose the first electrodes, liquid crystal material interposed between the first and the second electrodes to form a plurality of image elements at a plurality of positions corresponding to those points of the first and second electrodes which are opposed to each other, and a black mask for shielding light from leaking through clearances between the adjacent image elements. The image elements are arranged like a matrix and the black mask is formed discontinuous in the vertical and/or horizontal direction.