Micro gas chromatographic column with high depth-to-width ratio and wet corrosion manufacturing method thereof

Abstract

The invention discloses a high-aspect-ratio micro gas chromatographic column and a manufacturing method thereof by wet etching. The micro gas chromatographic column is made on a (110) single crystal silicon substrate to form a broken-line chromatographic groove, and the long and short sides of the broken line are The included angle is 70.53°, which are along the <110> and <112> crystal directions of the substrate, respectively. The zigzag chromatographic column adopts an anisotropic wet etching method to prepare vertical deep grooves with a high aspect ratio, and then is bonded with silicon glass, so that the entire zigzag groove has a high aspect ratio, and in a small area to achieve a sufficiently long column length. In terms of characteristic dimensions such as aspect ratio, column length, area, etc., the zigzag deep groove prepared by the present invention is equivalent to the vertical deep groove processed by DRIE, but the wet etching processing method adopted is simple and easy, and does not need to use expensive DRIE etching equipment greatly reduces processing costs.

Description

technical field [0001] The invention relates to the technical field of gas chromatography, in particular to a micro gas chromatography column with high aspect ratio and a manufacturing method thereof by wet etching. Background technique [0002] Gas chromatography is a technology for separating and identifying mixed gases. It was invented as early as the 1950s and is widely used in the fields of pharmaceuticals, oil exploration, environmental monitoring, material purification, and conventional organic compound analysis. [0003] A gas chromatograph is generally composed of a sample injector, a separation column, and a detector. The key component is the separation column, which determines the separation effect of the chromatograph. Traditional chromatographs mostly use quartz capillary as the separation column, and the inner wall of the separation column is coated or filled with a stationary phase. When the components of the mixture pass through the column with the carrier g...

AI Technical Summary

Problems solved by technology

However, dry etching requires special equipment and is expensive

As for the low-cost wet processing method, only the University of Cincinnati in the United States has achieved a simple straight-shaped deep groove structure, but its column length is only 3cm, which seriously affects the separation efficiency.

The general requirement of micro-chromatography is to achieve the highest possible chromatographic separation effect in a volume as small as possible. The straight structure will not bend or twist. Even if the length is increased, it will not meet the requirements of miniaturization.

However, the spiral and loop patterns commonly used in dry etching cannot obtain deep groove structures in wet etching.

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