US 2017/0363588 A1 · A MEMS Gas Chromatograph and Method of Forming a Separator Column for a MEMS Gas Chromatograph

Abstract

A micro gas chromatograph includes one or more separator columns formed within a device layer. The separator columns have small channel cross sections and long channel lengths with atomic-smooth channel sidewalls enabling a high channel packaging density, multiple channels positioned on top of each other, and channel segments that are thermally decoupled from the substrates. The micro gas-chromatograph also enables electrostatic and thermal actuators to be positioned in close proximity to the separator columns such that the material passing through the columns is one or more of locally heated, locally cooled, and electrically biased.

Claims20

Dependent claims

A method of forming a microelectromechanical system (MEMS) device, comprising:

providing a silicon-on-insulator (SOI) wafer including a base layer, a device layer above the base layer, and a buried oxide layer between the base layer and a lower surface of the device layer;
etching a plurality of trenches from an upper surface of the device layer to the buried oxide layer, the trenches spaced along a sequential path in the device layer;
releasing a portion of the buried oxide layer through the trenches;
and
annealing the SOI wafer to seal off the trenches at the upper and lower surfaces of the device layer so as to form (i) one or more atomic-smooth, continuous channels within the device layer and (ii) a cavity bounded by the base layer, the buried oxide layer, and the lower surface of the device layer.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application

15/535,522Filed 16 Dec 2015

Priority

17 Dec 2014

Published

21 Dec 2017

Term ends

Not estimatedThe source records don’t support an estimate.

Classification8 codes

G01N 30/6095
Construction of the column: micromachined or nanomachined, e.g. micro- or nanosize
B81B 1/002
Devices without movable or flexible elements, e.g. microcapillary devices: holes characterised by their shape, in either longitudinal or sectional…
B81C 1/00119
Without movable or flexible elements: arrangement of basic structures like cavities or channels, e.g. suitable for microfluidic systems
G01N 30/60
Column chromatography: construction of the column

A MEMS Gas Chromatograph and Method of Forming a Separator Column for a MEMS Gas Chromatograph

Life of this patent

A MEMS Gas Chromatograph and Method of Forming a Separator Column for a MEMS Gas Chromatograph

Life of this patent

Abstract

Claims20