Abstract: Applicants have found that energetic neutral particles created by a charged exchange interaction between high energy ions and neutral gas molecules reach the sample in a ion beam system using a plasma source. The energetic neutral create secondary electrons away from the beam impact point. Methods to solve the problem include differentially pumped chambers below the plasma source to reduce the opportunity for the ions to interact with gas.

Abstract: An inductively coupled plasma charged particle source for focused ion beam systems includes a plasma reaction chamber with a removably attached source electrode. A fastening mechanism connects the source electrode with the plasma reaction chamber and allows for a heat-conductive, vacuum seal to form. With a removable source electrode, improved serviceability and reuse of the plasma source tube are now possible.

Abstract: An inductively coupled plasma source for a focused charged particle beam system includes a conductive shield within the plasma chamber in order to reduce capacitative coupling to the plasma. The internal conductive shield is maintained at substantially the same potential as the plasma source by a biasing electrode or by the plasma. The internal shield allows for a wider variety of cooling methods on the exterior of the plasma chamber.

Abstract: An inductively coupled plasma charged particle source for focused ion beam systems includes a plasma reaction chamber with a removably attached source electrode. A fastening mechanism connects the source electrode with the plasma reaction chamber and allows for a heat-conductive, vacuum seal to form. With a removable source electrode, improved serviceability and reuse of the plasma source tube are now possible.

Abstract: An inductively coupled plasma ion source for a focused ion beam (FIB) system is disclosed, comprising an insulating plasma chamber with a feed gas delivery system, a compact radio frequency (RF) antenna coil positioned concentric to the plasma chamber and in proximity to, or in contact with, the outer diameter of the plasma chamber. In some embodiments, the plasma chamber is surrounded by a Faraday shield to prevent capacitive coupling between the RF voltage on the antenna and the plasma within the plasma chamber. High dielectric strength insulating tubing is heat shrunk onto the outer diameter of the conductive tubing or wire used to form the antenna to allow close packing of turns within the antenna coil. The insulating tubing is capable of standing off the RF voltage differences between different portions of the antenna, and between the antenna and the Faraday shield.

Abstract: A focused ion beam (FIB) system is disclosed, comprising an inductively coupled plasma ion source, an insulating plasma chamber containing the plasma, a conducting source biasing electrode in contact with the plasma and biased to a high voltage to control the ion beam energy at a sample, and a plurality of apertures. The plasma within the plasma chamber serves as a virtual source for an ion column comprising one or more lenses which form a focused ion beam on the surface of a sample to be imaged and/or FIB-processed. The plasma is initiated by a plasma igniter mounted near or at the column which induces a high voltage oscillatory pulse on the source biasing electrode. By mounting the plasma igniter near the column, capacitive effects of the cable connecting the source biasing electrode to the biasing power supply are minimized. Ion beam sputtering of the apertures is minimized by proper aperture materials selection.

Abstract: Applicants have found that energetic neutral particles created by a charged exchange interaction between high energy ions and neutral gas molecules reach the sample in a ion beam system using a plasma source. The energetic neutral create secondary electrons away from the beam impact point. Methods to solve the problem include differentially pumped chambers below the plasma source to reduce the opportunity for the ions to interact with gas.

Abstract: A method and apparatus for actively monitoring conditions of a plasma source for adjustment and control of the source and to detect the presence of unwanted contaminant species in a plasma reaction chamber. Preferred embodiments include a spectrometer used to quantify components of the plasma. A system controller is provided that uses feedback loops based on spectral analysis of the plasma to regulate the ion composition of the plasma source. The system also provides endpointing means based on spectral analysis to determine when cleaning of the plasma source is completed.

Abstract: An inductively coupled plasma charged particle source for focused ion beam systems includes a plasma reaction chamber with a removably attached source electrode. A fastening mechanism connects the source electrode with the plasma reaction chamber and allows for a heat-conductive, vacuum seal to form. With a removable source electrode, improved serviceability and reuse of the plasma source tube are now possible.

Abstract: A method for performing milling and imaging in a focused ion beam (FIB) system employing an inductively-coupled plasma ion source, wherein two sets of FIB system operating parameters are utilized: a first set representing optimized parameters for operating the FIB system in a milling mode, and a second set representing optimized parameters for operating in an imaging mode. These operating parameters may comprise the gas pressure in the ICP source, the RF power to the ICP source, the ion extraction voltage, and in some embodiments, various parameters within the FIB system ion column, including lens voltages and the beam-defining aperture diameter. An optimized milling process provides a maximum milling rate for bulk (low spatial resolution) rapid material removal from the surface of a substrate. An optimized imaging process provides minimized material removal and higher spatial resolutions for improved imaging of the substrate area being milled.

Abstract: An inductively coupled plasma source for a focused charged particle beam system includes a conductive shield within the plasma chamber in order to reduce capacitative coupling to the plasma. The internal conductive shield is maintained at substantially the same potential as the plasma source by a biasing electrode or by the plasma. The internal shield allows for a wider variety of cooling methods on the exterior of the plasma chamber.

Abstract: An inductively coupled plasma source for a focused charged particle beam system includes a dielectric liquid that insulates and cools the plasma chamber. A flow restrictor at an electrical potential that is a large fraction of the plasma potential reducing arcing because the voltage drop in the gas occurs primarily at relative high pressure.

Abstract: A method for performing milling and imaging in a focused ion beam (FIB) system employing an inductively-coupled plasma ion source, wherein two sets of FIB system operating parameters are utilized: a first set representing optimized parameters for operating the FIB system in a milling mode, and a second set representing optimized parameters for operating in an imaging mode. These operating parameters may comprise the gas pressure in the ICP source, the RF power to the ICP source, the ion extraction voltage, and in some embodiments, various parameters within the FIB system ion column, including lens voltages and the beam-defining aperture diameter. An optimized milling process provides a maximum milling rate for bulk (low spatial resolution) rapid material removal from the surface of a substrate. An optimized imaging process provides minimized material removal and higher spatial resolutions for improved imaging of the substrate area being milled.

Abstract: A method for performing milling and imaging in a focused ion beam (FIB) system employing an inductively-coupled plasma ion source, wherein two sets of FIB system operating parameters are utilized: a first set representing optimized parameters for operating the FIB system in a milling mode, and a second set representing optimized parameters for operating in an imaging mode. These operating parameters may comprise the gas pressure in the ICP source, the RF power to the ICP source, the ion extraction voltage, and in some embodiments, various parameters within the FIB system ion column, including lens voltages and the beam-defining aperture diameter. An optimized milling process provides a maximum milling rate for bulk (low spatial resolution) rapid material removal from the surface of a substrate. An optimized imaging process provides minimized material removal and higher spatial resolutions for improved imaging of the substrate area being milled.

Abstract: An inductively coupled plasma ion source for a focused ion beam (FIB) system is disclosed, comprising an insulating plasma chamber with a feed gas delivery system, a compact radio frequency (RF) antenna coil positioned concentric to the plasma chamber and in proximity to, or in contact with, the outer diameter of the plasma chamber. In some embodiments, the plasma chamber is surrounded by a Faraday shield to prevent capacitive coupling between the RF voltage on the antenna and the plasma within the plasma chamber. High dielectric strength insulating tubing is heat shrunk onto the outer diameter of the conductive tubing or wire used to form the antenna to allow close packing of turns within the antenna coil. The insulating tubing is capable of standing off the RF voltage differences between different portions of the antenna, and between the antenna and the Faraday shield.

Abstract: A focused ion beam (FIB) system is disclosed, comprising an inductively coupled plasma ion source, an insulating plasma chamber containing the plasma, a conducting source biasing electrode in contact with the plasma and biased to a high voltage to control the ion beam energy at a sample, and a plurality of apertures. The plasma within the plasma chamber serves as a virtual source for an ion column comprising one or more lenses which form a focused ion beam on the surface of a sample to be imaged and/or FIB-processed. The plasma is initiated by a plasma igniter mounted near or at the column which induces a high voltage oscillatory pulse on the source biasing electrode. By mounting the plasma igniter near the column, capacitive effects of the cable connecting the source biasing electrode to the biasing power supply are minimized. Ion beam sputtering of the apertures is minimized by proper aperture materials selection.

Abstract: A focused ion beam (FIB) system is disclosed, comprising an inductively coupled plasma ion source, an insulating plasma chamber containing the plasma, a conducting source biasing electrode in contact with the plasma and biased to a high voltage to control the ion beam energy at a sample, and a plurality of apertures. The plasma within the plasma chamber serves as a virtual source for an ion column comprising one or more lenses which form a focused ion beam on the surface of a sample to be imaged and/or FIB-processed. The plasma is initiated by a plasma igniter mounted near or at the column which induces a high voltage oscillatory pulse on the source biasing electrode. By mounting the plasma igniter near the column, capacitive effects of the cable connecting the source biasing electrode to the biasing power supply are minimized. Ion beam sputtering of the apertures is minimized by proper aperture materials selection.

Abstract: A focused ion beam (FIB) system is disclosed, comprising an inductively coupled plasma ion source, an insulating plasma chamber containing the plasma, a conducting source biasing electrode in contact with the plasma and biased to a high voltage to control the ion beam energy at a sample, and a plurality of apertures. The plasma within the plasma chamber serves as a virtual source for an ion column comprising one or more lenses which form a focused ion beam on the surface of a sample to be imaged and/or FIB-processed. The plasma is initiated by a plasma igniter mounted near or at the column which induces a high voltage oscillatory pulse on the source biasing electrode. By mounting the plasma igniter near the column, capacitive effects of the cable connecting the source biasing electrode to the biasing power supply are minimized. Ion beam sputtering of the apertures is minimized by proper aperture materials selection.

Abstract: A method for performing milling and imaging in a focused ion beam (FIB) system employing an inductively-coupled plasma ion source, wherein two sets of FIB system operating parameters are utilized: a first set representing optimized parameters for operating the FIB system in a milling mode, and a second set representing optimized parameters for operating in an imaging mode. These operating parameters may comprise the gas pressure in the ICP source, the RF power to the ICP source, the ion extraction voltage, and in some embodiments, various parameters within the FIB system ion column, including lens voltages and the beam-defining aperture diameter. An optimized milling process provides a maximum milling rate for bulk (low spatial resolution) rapid material removal from the surface of a substrate. An optimized imaging process provides minimized material removal and higher spatial resolutions for improved imaging of the substrate area being milled.