DEVICE AND METHOD FOR INTRODUCING GAS FOR ANALYSIS DEVICE

• US 20110000323A1
• Filed: 07/10/2008
• Published: 01/06/2011
• Est. Priority Date: 07/12/2007
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Sakai, Hisashi, Kishita, Keisuke
• Granted Patent: US 8,276,470 B2
• Time in Patent Office: Days
• US Class Current: 73/864.81
• CPC Class Codes: G01N 33/0011 Sample conditioning in general G01N1/28
• CPC Class Codes: H01J 2237/006 Details of gas supplies, e.g. in an ion source, to a beam line, to a specimen or to a workpiece, H01J37/3244 takes precedence; environmental cells for electron microscopes H01J2237/2003; microscopes with environmental specimen chamber H01J2237/2608
• CPC Class Codes: H01J 2237/182 Obtaining or maintaining desired pressure
• CPC Class Codes: H01J 2237/186 Valves
• CPC Class Codes: H01J 2237/188 Differential pressure
• CPC Class Codes: H01J 2237/2445 Photon detectors for X-rays, light, e.g. photomultipliers
• CPC Class Codes: H01J 2237/2446 Position sensitive detectors
• CPC Class Codes: H01J 37/18 Vacuum locks ; Means for obtaining or maintaining the desired pressure within the vessel vacuum locks for electron-beam tubes in general H01J29/865
• CPC Class Codes: H01J 37/244 Detectors; Associated components or circuits therefor
• CPC Class Codes: H01J 37/252 Tubes for spot-analysing by electron or ion beams; Microanalysers
• CPC Class Codes: H01J 37/26 Electron or ion microscopes; Electron or ion diffraction tubes
• CPC Class Codes: H01J 37/265 Controlling the tube; circuit arrangements adapted to a particular application not otherwise provided, e.g. bright-field-dark-field illumination

Abstract

Gas is supplied from positive pressure (10⁵ Pa or more) to an analysis device of high vacuum (10⁻² Pa or less) precisely and stably, while keeping conditions constant and replicating the conditions, and performing switching to a desired gas within a short time. According to a gas introducing device and a method, a plurality of types of gases are synthesized in a mixing chamber, the synthesized gas is introduced and the pressure of the gas is reduced by a pressure reducing pump to a pressure ranging from 0.1 Pa to 0.1 MPa, and the depressurized gas is introduced to a gas analysis device through a switching operation using a gas switching valve.

Claims

1. A device for introducing a gas for an analysis device, which includes:

a gas synthesis unit that synthesizes a plurality of types of gases in a mixing chamber;

a pressure adjusting unit that introduces the gas synthesized in the gas synthesis unit for pressure reduction;

a gas switching unit including a gas switching valve that performs switching so as to introduce the depressurized gas from the pressure adjusting unit to the gas analysis device, and a gas analysis device that analyses a component of the synthesized gas,

wherein the gas synthesis unit includes a plurality of gas introducing paths leading from a plurality of gas sources to the mixing chamber via a pressure valve, a path for exhaustion from the mixing chamber to exterior via an open/close valve, and a path for introduction from the mixing chamber to the pressure adjusting unit via a flow-adjusting valve,

wherein the pressure adjusting unit includes an introducing chamber that introduces gas from the gas synthesis unit, a path provided with a pump that reduces the pressure of the gas introduced in the introducing chamber to a pressure ranging from 0.1 Pa to 0.1 MPa, and a path leading from the introducing chamber to the gas switching unit, and

wherein the gas switching unit includes a path guiding the gas from the pressure adjusting unit to the analysis device via the gas switching valve, and a gas switching valve that performs switching so as to introduce the depressurized gas to the inside of the gas analysis device maintained at 10<sup>−

2</sup> Pa or less.

2. The device for introducing a gas according to claim 1, which is a device for introducing a gas for an analysis device, including a gas controlling unit, wherein the gas controlling unit controls the pressure valve of the gas synthesis unit so as to adjust the gas synthesized in the gas synthesis unit, controls the pump of the pressure adjusting unit so as to allow the pressure adjusting unit to reduce the pressure of the introduced gas to a desired pressure, and switches the gas switching valve to supply a desired type of gas to the analysis device.

3. The device for introducing a gas according to claim 2, which is a device for introducing a gas for an analysis device, wherein the gas control unit opens the pressure valve of the gas synthesis unit, drives the pump of the gas switching unit, and discharges a gas in the path from the mixing chamber to the switching valve in order to change a gas to be supplied to the analysis device.

4. The device for introducing a gas according to claim 2, which is a device for introducing a gas for an analysis device, wherein the gas switching valve introduces a desired gas in a desired path selected from among a plurality of paths to the analysis device.

5. A method for introducing a gas for an analysis device, comprising the steps of:

mixing a plurality of types of gasses in a mixing chamber of a gas synthesis unit;

adjusting the flow rate of the mixed gas so as to introduce the mixed gas to a pressure adjusting unit;

reducing the pressure of the introduced gas in the pressure adjusting unit with a pump to a preset pressure ranging from 0.1 Pa to 0.1 MPa; and

introducing the gas depressurized to the above pressure to the inside of the analysis device maintained at 10<sup>−

2</sup> Pa or less via a gas switching valve of a gas switching unit.