Leuven Instruments is pleased to announce that one of our invention patents, titled Gaseous Corrosion Cavity Capable of Adjusting Internal and External Pressure Difference and Gaseous Corrosion Method of Gaseous Corrosion Cavity (CN107610998A), is listed for the Excellence Award in last year’s 23rd China Patent Award Selection.

The China Patent Award is co-organized by the China National Intellectual Property Agency (CNIPA) and the World Intellectual Property Organization (WIPO). It is one of the most important intellectual property (IP) awards in China. In 2022, a total of 791 patents, including inventions and utility patents, were listed for the Excellence Award.

Trace metal analysis is one of the key quality control methods for wafer manufacturing, integrated circuit (IC) fabrication, and wafer reclaim. This is usually accomplished by collecting the elemental contaminants into a HF-containing H₂O microdroplet across the wafer surface using a vapor phase decomposition (VPD) equipment, followed by an inductively coupled plasma mass spectrometry (ICP-MS) analysis.

One of the most crucial design challenges for VPD systems lies in the imperative to balance the internal and external pressure of the vapor HF gas phase etching chamber (VHF chamber in short). The very first step of common VPD processes involves toxic gases such as hydrogen fluoride (HF) and tetrafluorosilane (SiF₄) as byproducts, because the native oxide of the silicon wafer must be removed with HF vapor in order to collect metallic contaminants with the microdroplet scanning solution in the subsequent process. Thus nitrogen purge gases of high flow rate (＞30 SLM) must be introduced before opening the VHD chamber. Usually, the VHF chamber is made of plastics to withstand the corrosive HF vapor. However, due to the low mechanical strength of the plastic material, if the pressure inside and outside the chamber is not balanced, the VHF chamber could be deformed over the pump–purge cycles during the processes. This might lead to toxic gases leaking out of the chamber. To ensure that the toxic HF gas is sealed inside the chamber, typically a high flow rate of purge gas is gradually into the chamber to prevent sudden spikes or dips in chamber pressure, at the cost of productivity. Thus the need arises for a mechanism to rapidly balance the pressure within and outside the VHF chamber of the VPD.

Through the aforementioned patent, Leuven Instruments came up with a smart gaseous corrosion cavity mechanism, which rapidly balances the pressure difference through a pumping control device. As such, the sample can be processed efficiently without the need to gradually adjust the cavity pressure. This design eliminates the gas leakage hazard without sacrificing productivity.

Winning the China Patent Excellence Award is both a significant milestone for our intellectual property work and a recognition for our endeavor in research and innovation. Leuven Instruments will continue to strive for engineering excellence and technical breakthroughs, and contribute our unique perspectives and know-hows to the semiconductor industry.

About Us

Leuven Instruments strives to provide the most reliable equipment and customized process solutions for 12-inch and 8-inch integrated circuit (IC) fabrication facilities (fabs). Our plasma etching, thin film deposition, and vapor phase decomposition systems support customers to address the critical challenges in logic, memory, power, optics, and micro-display device fabrication.