Device and method for drying supercritical carbon dioxide microemulsion

Abstract

The invention discloses a device and a method for drying supercritical carbon dioxide microemulsion. The method comprises the following steps of: displacing a water-based cleaning fluid by using liquid carbon dioxide; adding a surfactant; heating the carbon dioxide to reach a supercritical state; and drying a photoresist or a microstructure in a micro-electromechanical system (MEMS). In the method, because a gas-liquid interface and the surface tension are prevented, high depth-to-width ratio or porous structures and the like can be cleaned and dried without damage. Compared with the conventional supercritical carbon dioxide drying method, the method has the advantages that: an organic solution is not required to be used, so that the photoresist and the like cannot be damaged; the drying time is greatly reduced, so that the problem of pattern collapse can be effectively solved. The method meets the requirements of reducing the consumption of the organic solution, saving energy and thelike in an international semiconductor technology blueprint, and is easily compatible with the conventional integrated circuit (IC) process.

Description

technical field [0001] The invention relates to the technical field of semiconductor cleaning and drying, in particular to a supercritical carbon dioxide (SCCO 2 ) Apparatus and method for drying microemulsion. Background technique [0002] In the manufacturing process of microelectronic devices, with the further reduction of feature size and the further increase of structure complexity, the collapse of device structure has become an increasingly serious problem. When the devices cleaned with water as the main solvent are dried, the weaker mechanical structures such as micro-electro-mechanical components and photoresist patterns with high aspect ratios will be damaged. [0003] As an environmentally friendly and cheap solvent, carbon dioxide has a supercritical state with close to zero surface tension and high diffusivity, which is very suitable for semiconductor cleaning processes, so the 2006 International Semiconductor Technology Blueprint (ITRS) will supercritical Flui...

AI Technical Summary

Problems solved by technology

However, in order to avoid a certain amount of organic solution or water remaining in the device structure, it is often necessary to perform repeated pulse replacement, which is not only time-consuming, but also consumes a large amount of carbon dioxide.

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