Axcelis Technologies, Inc.

Robert D Rathmell

Victor M Benveniste

Bo H Vanderberg

William Davis Lee

Michael A Graf

Yongzhang Huang

Ashwin Madhukar Purohit

Allan D Weed

Eric R Harrington

Perry J I Justesen

Gary M Cook

Edward Eisner

Andrew M Ray

Douglas A Brown

Dennis Elliott Kamenitsa

David Hoglund

Youngzhang Huang

Aditya Agarwal

An electrostatic clamp is provided, having a clamping plate, wherein a clamping surface of the clamping plate is configured to contact the workpiece. A voltage applied to one or more electrodes selectively electrostatically attracts the workpiece to the clamping surface. One or more auxiliary clamping members are further provided wherein the one or more auxiliary clamping members are configured to selectively secure at least a portion of the workpiece to the clamping surface. A temperature monitoring device configured to determine a temperature of the workpiece is provided, and a controller is configured to selectively clamp the workpiece to the clamping surface via a control of the voltage to the one or more electrodes and the one or more auxiliary clamping members, based, at least in part, on the temperature of the workpiece.

Heated electrostatic chuck including mechanical clamp capability at high temperature

A clamping device and method is provided for securing first and second workpieces having different sizes to a clamping device and providing thermal conditioning thereto. An electrostatic clamping plate having a diameter associated with the first workpiece surrounds a central portion of the clamp. A non-electrostatic central portion provides a heater within the annulus, wherein the central portion has a diameter associated with the second workpiece. A workpiece carrier is provided, wherein the workpiece carrier is configured to hold the second workpiece above the heater, and wherein a diameter of the workpiece carrier is associated with the electrostatic clamping plate annulus. The annulus selectively electrostatically clamps the workpiece carrier or a circumferential portion of the first workpiece to its clamping surface, therein selectively maintaining a position of the first or second workpiece with respect to the annulus or non-electrostatic central portion.

Heated annulus chuck

An ion implanter for creating a ribbon or ribbon-like beam by having a scanning device that produces a side to side scanning of ions emitting by a source to provide a thin beam of ions moving into an implantation chamber. A workpiece support positions a workpiece within the implantation chamber and a drive moves the workpiece support up and down through the thin ribbon beam of ions perpendicular to the plane of the ribbon to achieve controlled beam processing of the workpiece. A control includes a first control output coupled to said scanning device to limit an extent of side to side scanning of the ion beam to less than a maximum amount and thereby limit ion processing of the workpiece to a specified region of the workpiece and a second control output coupled to the drive simultaneously limits an extent of up and down movement of the workpiece to less than a maximum amount and to cause the ion beam to impact a controlled portion of the workpiece.

Controlled dose ion implantation

A magnetic scanner employs constant magnetic fields to mitigate zero field effects. The scanner includes an upper pole piece and a lower pole piece that generate an oscillatory time varying magnetic field across a path of an ion beam and deflect the ion beam in a scan direction. A set of entrance magnets are positioned about an entrance of the scanner and generate a constant entrance magnetic field across the path of the ion beam. A set of exit magnets are positioned about an exit of the scanner and generate a constant exit magnetic field across the path of the ion beam.

System for magnetic scanning and correction of an ion beam

One or more aspects of the present invention pertain to stabilizing the current or density of an ion beam within an ion implantation system by selectively adjusting a lone parameter of feed gas flow. Adjusting the gas flow does not necessitate adjustments to other operating parameters and thereby simplifies the stabilization process. This allows the beam current to be stabilized relatively quickly so that ion implantation can begin promptly and continue uninterrupted. This improves throughput while reducing associated implantation costs.

Beam current stabilization utilizing gas feed control loop

One or more aspects of the present invention pertain to a measurement component that facilitates determining a relative orientation between an ion beam and a workpiece. The measurement component is sensitive to ion radiation and allows a relative orientation between the measurement component and the ion beam to be accurately determined by moving the measurement component relative to the ion beam. The measurement component is oriented at a known relationship relative to the workpiece so that a relative orientation between the workpiece and beam can be established. Knowing the relative orientation between the ion beam and workpiece allows the workpiece to be oriented to a specific angle relative to the measured beam angle for more accurate and precise doping of the workpiece, which enhances semiconductor fabrication.

Means to establish orientation of ion beam to wafer and correct angle errors

One or more aspects of the present invention pertain to determining a relative orientation between an ion beam and lattice structure of a workpiece into which ions are to be selectively implanted by the ion beam, and calibrating an ion implantation system in view of the relative orientation. The beam to lattice structure orientation is determined, at least in part, by directing a divergent ion beam at the workpiece and finding the angle of the aspect of the divergent beam that implants ions substantially parallel to crystal planes of the workpiece, and thus causes a small amount of damage to the lattice structure.

Ion implantation beam angle calibration

A lens structure for use with an ion beam implanter. The lens structure includes first and second electrodes spaced apart along a direction of ion movement. The lens structure extends across a width of the ion beam for deflecting ions entering the lens structure. The lens structure includes a first electrode for decelerating ions and a second electrode for accelerating the ions. A lens structure mode controller selectively activates either the accelerating or decelerating electrode to to cause ions entering the lens structure to exit said lens structure with a desired trajectory regardless of the trajectory ions enter the lens structure.

Electrostatic lens for ion beams

An ion implantation system having a dose cup located near a final energy bend of a scanned or ribbon-like ion beam of a serial ion implanter for providing an accurate ion current measurement associated with the dose of a workpiece or wafer. The system comprises an ion implanter having an ion beam source for producing a ribbon-like ion beam. The system further comprises an AEF system configured to filter an energy of the ribbon-like ion beam by bending the beam at a final energy bend. The AEF system further comprises an AEF dose cup associated with the AEF system and configured to measure ion beam current, the cup located substantially immediately following the final energy bend. An end station downstream of the AEF system is defined by a chamber wherein a workpiece is secured in place for movement relative to the ribbon-like ion beam for implantation of ions therein. The AEF dose cup is beneficially located up stream of the end station near the final energy bend mitigating pressure variations due to outgassing from implantation operations at the workpiece. Thus, the system provides accurate ion current measurement before such gases can produce substantial quantities of neutral particles in the ion beam, generally without the need for pressure compensation. Such dosimetry measurements may also be used to affect scan velocity to ensure uniform closed loop dose control in the presence of beam current changes from the ion source and outgassing from the workpiece.

Dose cup located near bend in final energy filter of serial implanter for closed loop dose control

Angular electrostatic filters and methods of filtering that remove energy contaminants from a ribbon shaped ion beam are disclosed. An angular electrostatic filter comprises a top deflection plate and a bottom deflection plate extending from an entrance side to an exit side of the filter. The bottom deflection plate is substantially parallel to the top deflection plate and includes an angle portion. An entrance focus electrode is positioned on the entrance side of the filter and an exit focus electrode is positioned on the exit side of the filter and both serve to focus the ion beam. Edge electrodes are positioned between the top and bottom deflection plates and at sides of the filter to mitigate edge effects. A negative bias is also applied to the top and bottom plates to mitigate space charge by elevating the beam energy.

Biased electrostatic deflector

The present invention facilitates semiconductor device fabrication by obtaining angle of incidence values and divergence of an ion beam normal to a plane of a scanned beam. A divergence detector comprising a mask and profiler/sensor is employed to obtain beamlets from the incoming ion beam and then to measure beam current at a number of vertical positions. These beam current measurements are then employed to provide the vertical angle of incidence values, which provide a vertical divergence profile that serves to characterize the ion beam. These values can be employed by an ion beam generation mechanism to perform adjustments on the generated ion beam or position of the workpiece if the values indicate deviation from desired values.

Device and method for measurement of beam angle and divergence

A magnetic deflector for an ion beam is disclosed and comprises first and second coils. The coils are positioned above and below the beam, respectively, and extend along a width of the beam. Current passes through the coils to generate a magnetic field therebetween that is generally perpendicular to a direction of travel of the beam along substantially the entire width thereof. In another aspect of the invention, a method of deflecting a beam prior to implantation into a workpiece is disclosed. The method includes determining one or more properties associated with the beam and selectively activating one of a magnetic deflection module and an electrostatic deflection module based on the determination.

Hybrid magnetic/electrostatic deflector for ion implantation systems

An accelerating structure and related method for accelerating/decelerating ions of an ion beam are disclosed. The structure and related method are suitable for use in selectively implanting ions into a workpiece or wafer during semiconductor fabrication to selectively dope areas of the wafer. In addition to accelerating and/or decelerating ions, aspects of the present invention serve to focus as well as to deflect ions of an ion beam. This is accomplished by routing the ion beam through electrodes having potentials developed thereacross. The ion beam is also decontaminated as electrically neutral contaminants within the beam are not affected by the potentials and continue on generally traveling along an original path of the ion beam. The electrodes are also arranged in such a fashion so as to minimize the distance the beam has to travel, thereby mitigating the opportunity for beam blow up.

Deflecting acceleration/deceleration gap

A lens structure for use with an ion beam implanter. The lens structure includes first and second electrodes spaced apart along a direction of ion movement. The lens structure extends on opposite sides of a beam path across a width of the ion beam for deflecting ions entering the lens structure. The lens structure include a first electrode for decelerating ions and a second electrode for accelerating the ions to cause ions entering the lens structure to exit said lens structure with approximately the same exit trajectory regardless of the trajectory ions enter the lens structure. In an alternate construction the lens structure can include a first electrode for accelerating ions and a second electrode for decelerating ions.

Electrostatic parallelizing lens for ion beams

A system for inhibiting the transport of contaminant particles with an ion beam includes a pair of electrodes that provide opposite electric fields through which the ion beam travels. A particle entrained in the ion beam is charged to a polarity matching the polarity of ion beam when traveling through a first of the electric fields. The downstream electrode provides another electric field for repelling the positively charged particle away from the direction of beam travel.

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Murphy, TX, United States of America

Robert D Rathmell