The following operators can be used to better focus your queries.
( ) , AND, OR, NOT, W/#
? single char wildcard, not at start
* multi char wildcard, not at start
(Cat? OR feline) AND NOT dog?
Cat? W/5 behavior
(Cat? OR feline) AND traits
Cat AND charact*
This guide provides a more detailed description of the syntax that is supported along with examples.
This search box also supports the look-up of an IP.com Digital Signature (also referred to as Fingerprint); enter the 72-, 48-, or 32-character code to retrieve details of the associated file or submission.
Concept Search - What can I type?
For a concept search, you can enter phrases, sentences, or full paragraphs in English. For example, copy and paste the abstract of a patent application or paragraphs from an article.
Concept search eliminates the need for complex Boolean syntax to inform retrieval. Our Semantic Gist engine uses advanced cognitive semantic analysis to extract the meaning of data. This reduces the chances of missing valuable information, that may result from traditional keyword searching.
The use of TEFLON* tape on the aluminum cathode of a reactive ion etching chamber eliminates unwanted formation of aluminum chloride on the etch sample anode.
English (United States)
This text was extracted from a PDF file.
100% of the total text.
Page 1 of 1
Method of Eliminating Aluminum Chloride Formation in an Aluminum
The use of TEFLON* tape on the aluminum cathode of a reactive ion etching
chamber eliminates unwanted formation of aluminum chloride on the etch sample
Chlorine based gases can be used to etch silicon in plasma reactors with
electrodes constructed of aluminum material. The process capability is limited by
the naturally formed aluminum oxide barrier that prevents a chemical reaction
between the chlorine and the aluminum. If etch times become excessive, the
aluminum oxide breaks down and aluminum chloride compounds are formed.
This material deposits on the etch sample surfaces, causing a non uniform etch.
In addition, this aluminum chloride material is hydroscopic and causes long pump
down cycles with the etcher.
When TEFLON material is used to coat the internal surfaces of the plasma
etch reactor, the material protects the metal surfaces from the chemical reaction
with the plasma. Chlorine containing gases can be used to etch silicon without
the aluminum chloride compound formation. Thus, system pump down times are
short, and etch depths are uniform.
Deep vertical grooves can be etched into silicon by this technique using
organic photoresist as an etch mask with good etch uniformity. * Trademark of E. I. du Pont de Nemours & Co.