Eaton Corporation

Axcelis Technologies, Inc.

Sony Corporation

Energy Sciences Inc.

A Stuart Denholm

Peter Lawrence Kellerman

William A Frutiger

Kenneth E Williams

Jiqun Shao

Michael A Graf

Jiong Chen

James D Bernstein

James P Quill

Kevin R Verrier

George Stejic

Jiong Cheng

G K Simcox

H F Glavish

A plasma immersion ion implantation method and system is provided for maintaining uniformity in implant energy distribution and for minimizing charge accumulation of an implanted substrate such as a wafer. A voltage modulator (,) applies a pulsed voltage signal (&minus;V,) to a platen (,) in a process chamber (,) containing a plasma, so that ions in the plasma are attracted by and implanted into a wafer residing on the platen. The voltage modulator (,) comprises: (i) a first switch (,) disposed between a power supply (,) and the platen for momentarily establishing a connection therebetween and supplying the pulsed voltage signal to the platen; (ii) a second switch (,) disposed between the platen (,) and ground for at least momentarily closing to discharge residual voltage (&minus;V,) from the platen after the first switch (,) opens and the connection between the power supply and the platen is broken; and (iii) a controller (,) for controlling sequential operation of the switches (,). By closing second switch (,) and grounding the platen, (a) only ions within a certain energy level range are implanted into the wafer, improving the implant energy distribution and (b) wafer charging due to implantation of positive ions is neutralized by allowing electrons in the plasma to flow toward the wafer between implant pulses. Upon opening, second switch (,) permits the platen to float to achieve the floating potential of the plasma thus minimizing voltage stresses on devices in the wafer. Alternatively, the platen may be positively biased to the plasma floating potential.

System for improving energy purity and implant consistency, and for minimizing charge accumulation of an implanted substrate

A dual walled exhaust assembly (,) is provided for an ion implantation system for connecting system components residing at differing voltage potentials. The assembly comprises a disposable corrugated inner tube (,) connected between inner mounting portions of a first end mount and a second end mount, and a permanent outer tube (,) connected between outer mounting portions of the first and second end mounts. The inner and outer tubes (,) are constructed from polytetrafluoroethylene (PTFE), or some similar dielectric material with appropriate non-flammable properties. The inner corrugated surface of the tube (,) has a plurality of surfaces which are pitched downwardly toward an axis (,) of the inner tube to prevent contaminant accumulation. The corrugated surface also reduces the risk of arcing between the system components residing at differing voltage levels by effectively increasing the length of the ground path that a leakage current would need to traverse across the length of the tube. The outer tube provides a containment mechanism for containing the toxic effluent if the thinner inner wall should puncture, perhaps due to electrical discharge which might still occur as a result of contaminant build-up on the inner surface of the inner tube.

Dual-walled exhaust tubing for vacuum pump

Apparatus and method for implanting ions into a workpiece surface. A concentration of ions is produced. An optical analysis of the concentration of ions is performed and recorded. The constituency of the ion concentration is determined by comparing the optical analysis data with a database of records on a storage medium wherein the optical analysis data for given concentrations of ions have been stored for subsequent access. Ions from the ion concentration are caused to impact a workpiece surface. The dose of ions implanted into the workpiece is measured. Implantation of the workpiece is stopped once an appropriate dose has been reached.

Ion implantation control using charge collection, optical emission

Method and apparatus for causing ions to impact a workpiece implantation surface. A process chamber defines a chamber interior into which one or more workpieces can be inserted for ion treatment. An energy source sets up an ion plasma within the process chamber. A support positions one or more workpieces within an interior region of the process chamber so that an implantation surface of the one or more workpieces is positioned within the ion plasma. A pulse generator in electrical communication with the workpiece support applies electrical pulses for attracting ions to the support. One or more dosimetry cups including an electrically biased ion collecting surface are disposed around the workpiece support to measure implantation current. An implantation controller monitors signals from the one or more dosimetry cups to control ion implantation of the workpiece.

Dosimetry cup charge collection in plasma immersion ion implantation

Method and apparatus for treating a workpiece implantation surface by causing ions to impact the workpiece implantation surface. An implantation chamber defines a chamber interior into which one or more workpieces can be inserted and includes a conductive inner wall portion in proximity to the chamber interior. A conductive workpiece support extends into an interior region of the implantation chamber. A conductive electrode is disposed within said implantation chamber relative to said conductive workpiece support to allow workpieces to be placed on the workpiece support in a region between the support and the conductive electrode. Gas molecules are injected into the implantation chamber to cause the gas molecules to occupy a region of the implantation chamber in close proximity to the one or more workpieces. The gas molecules are ionized near an implant surface of the workpieces. Control circuitry pulses the conductive electrode to a positive potential relative to the conductive workpiece support, the one or more workpieces, and the conductive wall portion of the implantation chamber. The control circuitry includes a voltage source that provides an electric field through which the ionized gas molecules accelerate before striking the implantation surfaces of the one or more workpieces.

Plasma immersion implantation with pulsed anode

Method and apparatus for treating a workpiece implantation surface by causing ions to impact the workpiece implantation surface. An implantation chamber defines a chamber interior into which one or more workpieces can be inserted. A support positions one or more workpieces within an interior region of the implantation chamber so that implantation surfaces of the workpieces are facing the interior region. A dopant material in the form of a gas is injected into the implantation chamber to cause the gas to occupy a region of the implantation chamber in close proximity to the one or more workpieces. A plasma of implantation material is created within the interior region of the implantation chamber. First and second conductive electrodes positioned within the implantation chamber include conductive surfaces in proximity to the chamber interior occupied by the one or more workpieces. A voltage source outside the chamber relatively biases the first and second conductive electrodes. A control circuit utilizes the voltage source for repeatedly relatively biasing the first and second conductive electrodes to energize the electrodes with a sequence of pulses that both ionize the gas molecules injected into the chamber and accelerate the ionized gas molecules toward the implantation surfaces of the one or more workpieces.

Pulsed plate plasma implantation system and method

An ion beam implanter having a remote ion beam collector to reduce particulate contamination in the region of the implant chamber. A resolving magnet is activated during implantation to bend ions that exit a source to a trajectory leading to an ion implantation chamber. By de-activating the resolving magnet when not implanting, ions from the source follow a linear path to the ion beam collector.

Ion beam implantation method and apparatus for particulate control

A radio frequency (rf) ion accelerator. A beam of ions enters the accelerator with a low initial velocity. Ions are accelerated to energies on the order of 1 mev per charge state for use in deep ion implantation of semiconductor materials. The accelerator is constructed from multiple stages or cells with each cell including an accelerating electrode coupled to an rf resonant tank circuit. The phase of the tank circuit oscillation is controlled to take into account the mass, charge, and initial velocity of the ion. After traversing the multiple cells, a focused beam of ions is directed to a workpiece.

Accelerator for ion implantation

This disclosure is concerned with the use of fine line converged electron beams of high aspect ratio for effecting physical, chemical, mechanical and other changes in the surface of objects, and also volume effects, including applications, for example, to semiconductor and other materials surface modification technology, annealing, welding, etching, polishing, cutting, curing and other surface and volume alteration.

Growing community of inventors

Lincoln, MA, United States of America

A Stuart Denholm