A high brightness plasma ion source has been developed to address focused ion beam ͑FIB͒ applications not satisfied by the liquid metal ion source ͑LMIS͒ based FIB. The plasma FIB described here is capable of satisfying applications requiring high mill rates ͑Ͼ100 m 3 / s͒ with non-gallium ions and has demonstrated imaging capabilities with sub-100-nm resolution. The virtual source size, angular intensity, mass spectra, and energy spread of the source have been determined with argon and xenon. This magnetically enhanced, inductively coupled plasma source has exhibited a reduced brightness ͑␤ r ͒ of 5.4ϫ 10 3 A m −2 sr −1 V −1 , with a full width half maximum axial energy spread ͑⌬E͒ of 10 eV when operated with argon. With xenon, ␤ r = 9.1 ϫ 10 3 A m −2 sr −1 V −1 and ⌬E = 7 eV. With these source parameters, an optical column with sufficient demagnification is capable of forming a sub-25-nm spot size at 30 keV and 1 pA. The angular intensity of this source is nominally three orders of magnitude greater than a LMIS making the source more amenable to creating high current focused beams, in the regime where spherical aberration dominates the LMIS-FIB. The source has been operated on a two lens ion column and has demonstrated a current density that exceeds that of the LMIS-FIB for current greater than 50 nA. Source lifetime and current stability are excellent with inert and reactive gases. Additionally, it should be possible to improve both the brightness and energy spread of this source, such that the ͑␤ r / ⌬E 2 ͒ figure-of-merit could be within an order of magnitude of a LMIS.

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A high performance ion source (Hyperion TM ) has been developed that significantly advances the capabilities of many ion beam techniques used by material scientists and engineers. Hyperion TM has been developed to provide focused beams as small as 10nm, beam currents up to several microamps and with a broad range of ion species that include He + , O 2 + , Xe + and H 3 + . This paper summarizes a few applications that have been explored with this new system, along with some of the enhanced capabilities anticipated for surface engineering, sample preparation and surface analysis. HyperionTM is a high density, non-thermal plasma ion source that exhibits very high brightness, low energy spread and is able to operate reliably with a broad range of ion species [1,2]. This technology provides state-of-the-art performance in many areas of surface science and engineering that include FIB Milling, Nano Implantation and High Resolution Surface Analysis.This new ion source provides a useable current that extends to many micro-amps with an energy normalized brightness of >1x10 4 Am -2 sr -1 V -1 with xenon, 6.7x10 3 Am -2 sr -1 V -1 with helium, 4.5x10 3 Am -2 sr -1 V -1 with oxygen and 2.7x10 3 Acm -2 sr -1 with hydrogen. Unlike point ion sources (eg the liquid-metal ion source), the effective beam brightness at the target can be maintained from picoAmps up to many micro-Amps. The combination of high brightness, low energy spread and very high angular intensity provides this broad range of operating currents. A comparison of the typical gallium FIB performance with the Hyperion TM FIB is shown in figure 1. Hyperion TM excels at beam currents >50nA, while still having the brightness to provide <25nm resolution for imaging at 30keV. This system finds a broad array of applications, that includes large area cross-sectioning of next generation 3D IC technologies. In the coming years, critical interconnects and vertically stacked circuitry will often need to be excavated by deep FIB milling for failure analysis. Figure 2 shows a cross-section of a 'Through Silicon Via' (TSV), anticipated in the industry to replace external wire interconnects for these new high density devices. Once the fabrication process has been further developed for these 3D devices, over 10 5 TSV's are anticipated for some stacked die.Applications such as prototyping MEMS and embedded circuit components have been demonstrated with this high current FIB. Figure 3 shows a micro-scale spiral RF antenna, often used on RF IC's, that has been fabricated here in <60 minutes. A 5µm thick layer of copper has been locally sputter deposited over a ~250x250µm area of silicon oxide with a 3µA Xe + beam hitting a copper target and creating a conformal deposit in ~25minutes. A bitmap has been uploaded to the FIB pattern generator, directing a 250nA, 25keV Xe + beam to mill away the excess copper. The deposited copper has a measured electrical conductivity that is within a factor of 3 of bulk copper, such that this 2.5nH (calculated) inductor would have a quality factor (Q) ...

Conventional focused ion beams (FIB) employing liquid metal ion sources (LMIS) are used to create site specific cross-sections for viewing subsurface features and performing 3D metrology on subsurface structure. Emerging applications incorporate novel materials as well as large structures that interface to decreasing IC dimensions and often require destructive physical analysis. This paper describes a novel instrument in which an inductively coupled plasma ion source is integrated onto a conventional FIB column. It compares this instrument to the existing LMIS FIBs and shows examples that illustrate the capabilities of this tool. This instrument retains the benefits of the conventional LMIS FIB such as high placement accuracy and the ability to immediately obtain high resolution images of the cross-section face without having to transfer it to another tool. It is capable of creating large cross-sections from 10 microns to 1mm in size at about 100 times faster than a conventional FIB.

HyperionTM is a newly developed high-performance ion source that significantly advances the capabilities of many ion beam techniques used by material scientists and engineers. Hyperion has been developed to provide focused beams as small as 10 nm, beam currents up to several micro-Amps, and a broad range of ion species that include He+, O2+, Xe+ and H3+.