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 particle therapy system, as one example of a particle beam irradiation system, comprises a charged particle beam generator and an irradiation field forming apparatus. An ion beam from the charged particle beam generator is irradiated to a diseased part in the body of a patient through the irradiation field forming apparatus. A scattering compensator and a range modulation wheel (RMW) are disposed on the upstream side in a direction of beam advance and are movable along a beam axis. The movement of the scattering compensator and the RMW adjusts a size of the ion beam entering a scatterer device, whereby a change in scattering intensity of the ion beam in the scatterer device is adjusted. As a result, a penumbra in dose distribution is reduced and a more uniform dose distribution in a direction perpendicular to the direction of beam advance is obtained in the diseased part.

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: A particle therapy system, as one example of a particle beam irradiation system, comprises a charged particle beam generator and an irradiation field forming apparatus. An ion beam from the charged particle beam generator is irradiated to a diseased part in the body of a patient through the irradiation field forming apparatus. A scattering compensator and a range modulation wheel (RMW) are disposed on the upstream side in a direction of beam advance and are movable along a beam axis. The movement of the scattering compensator and the RMW adjusts a size of the ion beam entering a scatterer device, whereby a change in scattering intensity of the ion beam in the scatterer device is adjusted. As a result, a penumbra in dose distribution is reduced and a more uniform dose distribution in a direction perpendicular to the direction of beam advance is obtained in the diseased part.

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 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 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 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 invention provides a charged particle therapy system capable of increasing the number of patients treated. An irradiation filed forming apparatus for irradiating a charged particle beam extracted from a charged particle beam generator to an irradiation target includes an RMW device. The RMW device comprises a housing and an RMW disposed within the housing. A rotary shaft of the RMW is rotatably mounted to the housing. The RMW device is detachably installed in an RMW holding member provided in a casing of the irradiation filed forming apparatus. The housing can be placed in contact with the RMW holding member, and hence positioning of the rotary shaft of the RMW to a predetermined position can be performed in a short time. This contributes to cutting a time required for treatment per patient and increasing the number of patients treated.

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: 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: Particle beam irradiation equipment and a method of adjusting irradiation nozzle, which can ensure a long range and high dose uniformity at any field size are provided. The particle beam irradiation equipment comprises charged particle beam generation equipment and an irradiation nozzle for irradiating a charged particle beam extracted from the charged particle beam generation equipment to an irradiation target. The irradiation nozzle comprises a first scatterer device including a first scatterer for spreading out the charged particle beam into a Gaussian-like distribution, and multiple stages of second scatterer devices including second scatterers for producing a uniform intensity distribution of the charged particle beam having been spread out into a Gaussian-like distribution by the first scatterer.

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: 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 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: This invention provides a double hetero-junction bipolar transistor (DHBT) in which a probability of the impact ionization at the interface between the base and the collector is reduced, thereby enhancing the break down voltage. In the present DHBT, a plurality of transition layers is inserted between the base layer and the collector layer. Each transition layers has an energy band gap gradually increasing from the base to the collector, and comprises a doped layer close to the base and an un-doped layer. Transition layers thus configured may bring both characteristics of the high break down voltage by the reduction of the average doping concentration and the capability of the high-speed operation by the reduction of the junction capacitance.

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 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: 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.