Patent classifications
H01J37/08
CONTROLLER AND CONTROL TECHNIQUES FOR LINEAR ACCELERATOR AND ION IMPLANTER HAVING LINEAR ACCELARATOR
An apparatus may include global control module, the global control module including a digital master clock generator and a master waveform generator. The apparatus may also include a plurality of resonator control modules, coupled to the global control module. A given resonator control module of the plurality of resonator control modules may include a synchronization module, having a first input coupled to receive a resonator output voltage pickup signal from a local resonator, a second input coupled to receive a digital master clock signal from the digital master clock generator, and a first output coupled to send a delay signal to the master waveform generator.
ION EXTRACTION ASSEMBLY HAVING VARIABLE ELECTRODE THICKNESS FOR BEAM UNIFORMITY CONTROL
An ion extraction assembly for an ion source is provided. The ion extraction assembly may include a plurality of electrodes, wherein the plurality of electrodes comprises: a plasma-facing electrode, arranged for coupling to a plasma chamber; and a substrate-facing electrode, disposed outside of the plasma-facing electrode. The at least one electrode of the plurality of electrodes may include a grid structure, defining a plurality of holes, wherein the at least one electrode has a non-uniform thickness, wherein a first grid thickness in a middle region of the at least one electrode is different than a second grid thickness, in an outer region of the at least one electrode.
Mismatched Optics for Angular Control of Extracted Ion Beam
An ion source capable of extracting a ribbon ion beam with improved vertical angular uniformity is disclosed. The extraction plate and extraction optics are designed such that there is at least one non-uniform gap between adjacent components. A non-uniform gap may be effective in reducing angular spread non-uniformity of the extracted ribbon ion beam. Specifically, for a given gap in the Z direction, ions extracted from regions with lower plasma density may have more vertical angular spread. A larger gap in the Z direction between components in this region may make the vertical angular spread closer to the vertical angular spread of ions extracted from regions with higher plasma density. The non-uniform gap may be created by having an extraction plate that is flat or curved and electrodes that are flat, convex or concave. In certain embodiments, the non-uniform gap is located between the extraction plate and the suppression electrode.
Mismatched Optics for Angular Control of Extracted Ion Beam
An ion source capable of extracting a ribbon ion beam with improved vertical angular uniformity is disclosed. The extraction plate and extraction optics are designed such that there is at least one non-uniform gap between adjacent components. A non-uniform gap may be effective in reducing angular spread non-uniformity of the extracted ribbon ion beam. Specifically, for a given gap in the Z direction, ions extracted from regions with lower plasma density may have more vertical angular spread. A larger gap in the Z direction between components in this region may make the vertical angular spread closer to the vertical angular spread of ions extracted from regions with higher plasma density. The non-uniform gap may be created by having an extraction plate that is flat or curved and electrodes that are flat, convex or concave. In certain embodiments, the non-uniform gap is located between the extraction plate and the suppression electrode.
Ion source with biased extraction plate
An ion source having an electrically isolated extraction plate is disclosed. By isolating the extraction plate, a different voltage can be applied to the extraction plate than to the body of the arc chamber. By applying a more positive voltage to the extraction plate, more efficient ion source operation with higher plasma density can be achieved. In this mode the plasma potential is increased, and the electrostatic sheath reduces losses of electrons to the chamber walls. By applying a more negative voltage, an ion rich sheath adjacent to the extraction aperture can be created. In this mode, conditioning and cleaning of the extraction plate is achieved via ion bombardment. Further, in certain embodiments, the voltage applied to the extraction plate can be pulsed to allow ion extraction and cleaning to occur simultaneously.
Ion source with biased extraction plate
An ion source having an electrically isolated extraction plate is disclosed. By isolating the extraction plate, a different voltage can be applied to the extraction plate than to the body of the arc chamber. By applying a more positive voltage to the extraction plate, more efficient ion source operation with higher plasma density can be achieved. In this mode the plasma potential is increased, and the electrostatic sheath reduces losses of electrons to the chamber walls. By applying a more negative voltage, an ion rich sheath adjacent to the extraction aperture can be created. In this mode, conditioning and cleaning of the extraction plate is achieved via ion bombardment. Further, in certain embodiments, the voltage applied to the extraction plate can be pulsed to allow ion extraction and cleaning to occur simultaneously.
Ion source with single-slot tubular cathode
An ion source including a chamber housing defining an ion source chamber and including an extraction plate on a front side thereof, the extraction plate having an extraction aperture formed therein, and a tubular cathode disposed within the ion source chamber and having an opening formed in a front half thereof nearest the extraction aperture, wherein a rear half of the tubular cathode furthest from the extraction aperture is closed.
Temperature control for insertable target holder for solid dopant materials
An ion source with a target holder for holding a solid dopant material is disclosed. The ion source comprises a thermocouple disposed proximate the target holder to monitor the temperature of the solid dopant material. In certain embodiments, a controller uses this temperature information to vary one or more parameters of the ion source, such as arc voltage, cathode bias voltage, extracted beam current, or the position of the target holder within the arc chamber. Various embodiments showing the connections between the controller and the thermocouple are shown. Further, embodiments showing various placement of the thermocouple on the target holder are also presented.
Temperature control for insertable target holder for solid dopant materials
An ion source with a target holder for holding a solid dopant material is disclosed. The ion source comprises a thermocouple disposed proximate the target holder to monitor the temperature of the solid dopant material. In certain embodiments, a controller uses this temperature information to vary one or more parameters of the ion source, such as arc voltage, cathode bias voltage, extracted beam current, or the position of the target holder within the arc chamber. Various embodiments showing the connections between the controller and the thermocouple are shown. Further, embodiments showing various placement of the thermocouple on the target holder are also presented.
Extended cathode and repeller life by active management of halogen cycle
A system and method for extending the life of a cathode and repeller in an IHC ion source is disclosed. The system monitors the health of the cathode by operating using a known set of parameters and measuring the bias power used to generate the desired extracted beam current or the desired current from the arc voltage power supply. Based on the measured bias power, the system may determine whether the cathode is becoming too thin, and may take a corrective action. This corrective action may be to alert the operator; to operate the IHC ion source using a predetermined set of parameters; or to change the dilution used within the IHC source. By performing these actions, the life of the cathode may be more than doubled.