William D Knowles

7541580, Jun 2, 2009

Mar 30, 2007

11/731743

William Ralph Knowles - Forest Grove OR, US
Milos Toth - Cambridge MA, US

FEI Company - Hillsboro OR

H01J 37/252

250310

A detector for use with a high pressure SEM, such as an ESEM environmental SEM from FEI Company, extends the effective detection space above the PLA, thereby increasing secondary signal amplification without increasing working distance or pressure. Embodiments can therefore provide improved resolution and can operate at lower gas pressures.

7718979, May 18, 2010

Feb 6, 2008

12/027245

William Ralph Knowles - Forest Grove OR, US

FEI Company - Hillsboro OR

A61N 5/00

2504921, 2504923

A particle-optical apparatus, such as an ESEM, for simultaneous observing a sample with particles and photons. A pressure limiting aperture (PLA) is placed in a diaphragm between the objective lens of the ESEM and the sample position. The distance between the sample position and the aperture is sufficiently small to allow a large collection angle of the photons through this aperture. A mirror is placed between the diaphragm and the objective lens. Due to the large collection angle for photons a large NA is achieved. The small distance between sample position and aperture also result in less scattering of electrons than occurs in ESEM's where a mirror is placed between aperture and sample position, as the electrons have to travel through only a limited length in a high pressure area. Embodiments describe combinations where e. g. an immersion lens is used.

7791020, Sep 7, 2010

Mar 31, 2008

12/059850

Marek Uncovsky - Brno, CZ
Milos Toth - Portland OR, US
William Ralph Knowles - Forest Grove OR, US

FEI Company - Hillsboro OR

H01J 37/244
H01J 37/28
H01J 37/252

250306, 250307, 250309, 250310

A novel detector for a charged particle beam system which includes multiple gas amplification stages. The stages are typically defined by conductors to which voltage are applied relative to the sample or to a previous stage. By creating cascades of secondary electrons in multiple stages, the gain can be increased without causing dielectric breakdown of the gas.

8299432, Oct 30, 2012

Nov 4, 2008

12/264805

Milos Toth - Portland OR, US
William Ralph Knowles - Hillsboro OR, US
Rae Knowles, legal representative - Hillsboro OR, US

FEI Company - Hillsboro OR

G01N 23/00

250311, 250306, 250307, 250309, 2504921, 2504923

A scanning transmission electron microscope operated with the sample in a high pressure environment. A preferred detector uses gas amplification by converting either scattered or unscattered transmitted electrons to secondary electrons for efficient gas amplification.

20110031394, Feb 10, 2011

Feb 6, 2008

12/525908

William Ralph Knowles - Hillsboro OR, US
Rae Knowles - HillsBoro OR, US
Milos Toth - Portland OR, US

FEI COMPANY - HILLSBORO OR

G01N 23/00

250307, 250310

The current invention includes methods and apparatuses for processing, that is, altering and imaging, a sample in a high pressure charged particle beam system. Embodiments of the invention include a cell in which the sample is positioned during high pressure charged particle beam processing. The cell reduces the amount of gas required for processing, thereby allowing rapid introduction, exhaustion, and switching between gases and between processing and imaging modes. Maintaining the processes gases within the cell protects the sample chamber and column from contact with the gases. In some embodiments, the temperature of the cell walls and the sample can be controlled.