Micromachined mass spectrometer
AssigneeRosemount Analytical Inc.
InventorFred C. Sittler
Life of this patent
Estimating the term…
Abstract
A micromachined mass spectrometer includes an ionizer, a separation region and a detector. The ionizer is formed from an upper electrode, a center electrode and a lower electrode. Ionization of a sample gas takes place around an edge of the center electrode. Accelerating electrodes extract ionized particles from the ionizer. Ionized particles are accelerated through the separation region. A magnetic field is applied in a direction perpendicular to travel of the ionized particles through the separation region causing the trajectory of the ionized particles to bend. The mass spectrometer is formed using micromachined techniques and is carried on a single substrate.
Claims32
A device for ionizing at least a portion of a fluid sample, the device comprising:
- a substrate having a substantially planar surface;
- a first electrode carried by the planar surface and having an edge
- a second electrode carried by the planar surface;
- and
- wherein the second electrode has a portion spaced-apart from the substrate, the portion being positioned proximate the first electrode such that an electric potential applied across the first and second electrodes ionizes a portion of the fluid sample proximate the edge.
A device for ionizing at least a portion of a fluid sample, the device comprising:
- a substrate having a substantially planar surface;
- a first and second electrode carried by the planar surface;
- wherein the first electrode has a portion spaced-apart from the substrate, the portion being positioned proximate the second electrode such that an electric potential applied across the first and second electrodes ionizes said at least a portion of the fluid sample;
- and
- wherein at least a portion of the second electrode is adjacent to the fluid sample and positioned between the first electrode and the substrate.
A mass spectrometer for analyzing a sample composed of particles having particle masses, the spectrometer comprising:
- a substrate;
- an ionizer receiving the sample and ionizing at least some of the particles, the ionized particles having charge-to-mass ratios;
- an ion detector disposed on the substrate to receive a portion of the ionized particles from the ionizer, the ion detector being separated from the ionizer by a region of space through which the ionized particles travel;
- a plurality of field generators which generate an electric and magnetic field in the region of space;
- and
- wherein the electric and magnetic fields cause the ionized particles to strike the substrate at zones positioned on the substrate substantially in proportion to the charge-to-mass ratios of the ionized particles.
A method for analyzing a sample composed of particles having particle masses, comprising the steps of:
- ionizing at least some of the particles with an ionizer, the ionized particles having charge-to-mass ratios;
- collecting a portion of the ionized particles at an ion detector, the portion being those ionized particles which have a value of charge-to-mass ratio (CMR) within a resolution limit of a desired charge-to-mass ratio, the ion detector being separated from the ionizer by a region of space through which the ionized particles travel;
- providing at least one of an electric field and a magnetic field in the region of space;
- selecting the desired charge-to-mass ratio from a first and second CMR value by adjusting the at least one of an electric field and a magnetic field, the ion detector resolution limit having a first and second limit value corresponding to the first and second CMR value, respectively;
- wherein the first CMR value is equal to the second CMR value multiplied by a factor "X", X having a value greater than one;
- and
- wherein the at least one of an electric field and a magnetic field is arranged such that a ratio of the first limit value to the second limit value is less than the square root of X.
A mass spectrometer, comprising:
- a micromachined ionizer;
- a micromachined ion detector;
- and
- a substrate holding the ionizer and the ion detector in a spaced-apart relationship.
A mass spectrometer, comprising:
- an ionizer;
- a substrate adjacent the ionizer, the substrate formed from a brittle material;
- and
- an ion detector micromachined from the substrate to detect ions from the ionizer.
A method of fabricating a mass spectrometer, comprising the steps of:
- providing a first and second substrate;
- forming an ionizer on the first substrate and an ion detector on the second substrate.
A method of fabricating a mass spectrometer, comprising the steps of:
- providing a first and second substrate;
- forming an ionizer on the first substrate and an ion detector on the second substrate;
- and
- coupling the first substrate to the second substrate to establish a predetermined separation between the ionizer and the ion detector.
A device for ionizing at least a portion of a fluid sample, the device comprising:
- a substrate;
- a first electrode carried by the substrate and having an edge elongated along a line substantially parallel to the substrate and adjacent to the fluid sample;
- a second electrode carried by the substrate;
- and
- a third electrode proximate the first electrode wherein the first electrode is positioned between the second and third electrodes, the third electrode being disposed proximate the first electrode such that an electric potential applied across the first and third electrodes ionizes a portion of the fluid sample proximate the edge.
A device for ionizing at least a portion of a fluid sample, the device comprising:
- a substrate;
- a first and second electrode carried by the substrate;
- and
- a third electrode carried by the substrate and disposed at least partially between a portion of the second electrode and the substrate, the first, second, and third electrodes being disposed such that an electric potential applied therebetween ionizes a portion of the fluid sample proximate the portion of the second electrode.
Dependencies are inferred from the claim text.