摘要:
A microwave ion source suitable for an apparatus which requires ions of an element of high reactivity such as oxygen, fluorine, etc., the microwave ion source being arranged to transmit microwaves between outer and inner conductors of a coaxial line. An ion extraction electrode is formed at least partly of a low magnetic permeability material while an acceleration electrode is formed of a high magnetic permeability material. The acceleration electrode is formed so as to have a structure in which a low magnetic permeability material of a certain thickness is stacked on the high magnetic permeability material at a plasma chamber side and openings of ion exit holes are formed in the portion of the low magnetic permeability material. A permanent magnet constituting a magnetic field generating means is provided to surround the microwave lead-in coaxial line. The direction of magnetization of the permanent magnet is made to coincide with the axial direction of the coaxial line. The end surface of the permanent magnet at the microwave lead-in side is coupled with the periphery of the high magnetic permeability material of the acceleration electrode through another high magnetic permeability material to form a magnetic path. The plasma chamber is formed of a dielectric insulator which transmits microwaves well. It is possible to realize an ion source in which ions can be extracted with a high electric field, and in which a high current ion beam can be extracted for a long time.
摘要:
An Mev ion implantation apparatus which does not contaminate a sample substrate with heavy metal particles. The apparatus includes an external resonance circuit type RFQ accelerator incluidng undulated quadrupole electrodes and a separate radio frequency resonance circuit for generating a radio frequency high voltage to be supplied to the electrodes. The undulated quadrupole electrodes and at least a part of metallic supports for supporting the electrodes and voltage supplying lines are provided with a surface coating of silicon, silicon doped with an impurity such as boron, phosphorus, or arsenic, or a light element having a mass number of 28 or less, such as carbon.
摘要:
A secondary coil forming a resonant circuit in cooperation with a quadrupole is composed of conductive tubes and cooled by feeding coolant such as pure water into the tubes which serve as coolant passages. This makes it possible to minimize thermal deformation of the secondary coil when a variable-frequency type radio-frequency quadrupole accelerator is driven with a large amount of power. As a result, variation of the resonant frequency of the resonant circuit, resulting from the deformation of the secondary coil, can be minimized. Consequently, a given ion acceleration ability can be provided. When a coolant passage for use in cooling the primary coil is included and coolant such as pure water is fed into the coolant passage, thermal deformation of the primary coil can be minimized. Thus, impedance matching with the resonant circuit can be maintained on a stable basis. When the secondary coil is made by aligning several unit secondary coils in the axial direction of the quadrupole, the resonant frequency can be varied by mounting or dismounting the unit secondary coils independently.
摘要:
An ion implanting apparatus includes a magnetic quadrupole lens disposed between an ion source and an RFQ accelerator. The magnetic quadrupole lens carries out mass spectrometry of an ion beam extracted from the ion source while converging the ion beam, and reduces the divergence of the ion beam due to the space charge effect as compared to an electrostatic quadrupole lens. The use of the magnetic quadrupole lens makes it possible to utilize to a maximum extent the ion beam extracted from the ion source and to restrict to a minimum the reduction in the current of the ion beam during passage of the ion beam, thereby making it possible to generate a high-energy ion beam having a large current on the order of several tens of milliamperes.
摘要:
An ion source equipped with an ion beam exit slit for extracting ions from plasma generated in feed gas introduced into a discharge chamber, and with gas inlet or inlets for introducing the feed gas into the discharge chamber in close proximity of the ion beam exit slit. Ion extraction can be made stably without any deposit on the ion beam exit slit even when a boron halide is used as the feed gas. The effect of the ion source can be further enhanced by adding oxygen, hydrogen or gas of an oxygen-containing compound to the feed gas, and by using a microwave.
摘要:
A microwave discharge ion source according to this invention comprises a microwave generator, a discharge chamber having ridged electrodes, and a waveguide connecting the microwave generator with the discharge chamber. This waveguide consists of a waveguide having no ridged electrode, and a waveguide having ridged electrodes. Further, a vacuum-sealing dielectric plate is disposed at an intermediate position or an end part of the waveguide having no ridged electrode. A space in the waveguide as extends from the vacuum-sealing dielectric plate to the discharge chamber is filled with a dielectric.As a result, the design and fabrication of the vacuum-sealing dielectric plate are facilitated, and a microwave discharge ion source of high performance is provided.
摘要:
A plasma ion source includes a discharge chamber in which a plasma is produced by plasma generator, with an acceleration electrode being disposed adjacent to the discharge chamber in order to extract ions from the produced plasma. A deceleration electrode is disposed adjacent to the acceleration electrode to decelerate the extracted ions, and a ground electrode is disposed adjacent to the deceleration electrode. An insulator container is disposed so as to surround the discharge chamber and the respective electrodes, and a shield ring electrode of ground potential is disposed in the vicinity of the deceleration electrode and along an inner wall surface of the insulator container in order to prevent any discharge from arising across the deceleration electrode and the ground electrode.
摘要:
In a microwave plasma source, a discharge space supplied with a microwave electric field is supplied with a DC magnetic field. A material to be ionized is introduced into the discharge space to produce plasma, whereby ions are extracted through an ion extracting system. A switch is provided for effecting through switching operation the change-over of the magnetic field applied to the discharge space from the intensity for the ignition of plasma to the intensity for ion extraction in succession to completion of the plasma ignition.
摘要:
A charged particle accelerator is provided with quadrupole electrodes with surfaces that are opposed to each other and are undulated, and with an external resonance circuit. The external resonance circuit consists of a capacitor formed by the opposing electrodes, a variable capacitor provided in parallel with said capacitor, and a coil. The resonance frequency is variable. A direct current and an alternating current may be applied in a superposed manner to the quadrupole electrodes. The thus constructed accelerator can be employed for an ion implanter to implant a heavy-current ion beam of several hundred KeV to several MeV.
摘要:
In order to implant ions uniformly in a plurality of wafers, carriers, on which a plurality of wafers are mounted, are moved along a straight line one after another. An ion implanter comprises a beam sweep width controller for controlling the beam sweep width in such a manner that the area scanned with the ion beam by sweeping it coincides approximately with the shape of the wafers in which ions are to be implanted and a carrier speed controller for controlling the carrier speed, depending on the beam sweep width so that the dose of ions implanted in the wafers is uniform. The beam sweep width controller includes a detector for detecting the width of a wafer in which ions are being implanted in the one direction and a controller for varying the beam sweep width, depending on the width of the wafer thus detected. The carrier speed controller varies the carrier speed inversely proportionally to the width of the wafer thus detected.