Removal of metal contaminants from ultra-high purity gases
An ultra-high-purity, pollutant technology, used in inert gas compounds, gas treatment, non-metallic elements, etc., can solve problems such as defective device performance, and achieve the effect of fewer defective products and increased product stability
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Publication Date
- 2007-06-27
- Estimated Expiration
- Not applicable · inactive patent
Smart Images
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Abstract
Description
technical field
[0001] This application claims priority to US Provisional Patent Application Serial No. 60 / 589,695, filed July 20, 2004, the entire teachings of which are incorporated herein by reference. Background technique
[0002] Metal impurities are particularly problematic in the manufacture of electronic devices such as semiconductors, liquid crystal displays, and optoelectronic and photonic devices. Electrical properties such as conductivity, resistance, permittivity, and photoluminescence are important to the performance of these devices. Small concentrations of metallic impurities have a profound effect on these properties, since metals are generally more conductive than the device material, either at the Fermi level or as sole charge carriers. The effect of metal concentration on the electrical properties of many semiconductor materials has been extensively studied in the published literature.
[0003] In addition to electrical properties, metallic impurities a...
Examples
Embodiment 1
[0037] Example 1: Purification of 10 Metal Contaminants from Copper Piping Systems
[0038] Individual pairs of silicon wafers were subjected to three different environments and subsequently analyzed for the presence of 10 selected metal contaminants with vapor phase decomposition using inductively coupled plasma mass spectrometry (VPD-ICP-MS). Each pair of wafers was flooded with nitrogen and stored in high-purity shipping boxes, triple-sealed with plastic bags and cleanroom tape until use.
[0039] The first pair of silicon wafers was checked for metal contamination using VPD-ICP-MS immediately after removal from the storage box.
[0040] A second pair of silicon wafers was placed in a Class 100 laminar flow hood. Pass high-purity nitrogen through hundreds of feet of copper piping. The gas is then passed through a gas purifier at a volumetric flow rate of less than 60 standard liters per minute (slm), wherein the purifying material is nickel / nickel oxide embedded on a si...
Embodiment 2
[0047] Example 2: Removal of Iron(III) Chloride from a Nitrogen Stream
[0048] Conducting experiments to evaluate purification materials for removal of FeCl from nitrogen streams 3 Ability. Experiments were carried out using a test system 300 schematically shown in FIG. 3 .
[0049] Nitrogen is added to system 300 via line 310 . Fill approximately 40 mL of iron(III) chloride into enclosure 320, providing FeCl to be encased in a nitrogen test stream. 3 source. Wrap a heating mantle around the shell 320 and heat to 200°C to assist the FeCl 3 Bracketed in a stream of nitrogen.
[0050] Connected in parallel to the outlet line of the housing 320 are two sets 341 , 342 comprising three Teflon collection bottles respectively. Each Teflon collection bottle was pre-rinsed and filled with 2% dilute nitric acid solution to capture metal impurities. Each set of bottles is arranged in series. Valves 361, 362 respectively control the entrainment of FeCl 3 The nitrogen flow into...