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Roslin, United Kingdom

Millar S.,Heriot - Watt University | Desmulliez M.P.Y.,Heriot - Watt University | McCracken S.,MCS Ltd
Microsystem Technologies | Year: 2011

This paper presents the limitations of the helium leak test when applied to typical MEMS packages. A novel closed-form expression is presented which allows the determination of the minimum cavity volume package that can be accurately tested using the helium leak test method in conjunction with a standard gross leak test. This expression can be used to find optimum test parameters for packages with cavity volumes greater than 2.6 × 10-3 cm 3. Hermeticity testing using FTIR and Raman spectroscopy are considered as potential methods to overcome the limitations of the helium leak test method. © Springer-Verlag 2010. Source

Costello S.,Heriot - Watt University | Desmulliez M.P.Y.,Heriot - Watt University | McCracken S.,MCS Ltd | Lowrie C.,Heriot - Watt University | And 2 more authors.
IEEE International Conference on Microelectronic Test Structures | Year: 2012

This paper details the design, fabrication and characterisation of a piezoresistive membrane deflection test structure for the electrical evaluation of hermeticity in low cavity volume package. This test structure uses the 0-level silicon cap, defined in the MultiMEMS foundry service, as a deflecting membrane to electrically monitor changes in package cavity pressure over time. The hermeticity of the package can then be determined in real-time and low leak rates can be measured using a pressurisation stage, which also accelerates the test. The minimum detectable leak rate of the test structure without test acceleration is 6.9×10 12 atm.cm 3.s 1, which is two orders of magnitude lower than the limit of the traditional helium fine leak test method. © 2012 IEEE. Source

Zuzaan P.,National University of Mongolia | Gansukh N.,MCS Ltd | Bolortuya D.,National University of Mongolia
X-Ray Spectrometry | Year: 2010

In this paper an analytical procedure for the determination of La, Ce, Pr and Nd in rare-earth ores is described. More than 5000 of powdered samples were prepared from the ores selected in various places of their deposit. The samples were analyzed by energy-dispersive X-ray fluorescence (EDXRF) with an Am-241 source for the radiation excitation of characteristic K-lines of the elements mentioned. The results were compared with the data of other methods and reference materials. The correlation of La-Ce, La-Pr, La-Nd, Ce-Pr, Ce-Nd and Pr-Nd elements pairs were determined. © 2009 John Wiley & Sons, Ltd. Source

Millar S.,Heriot - Watt University | Desmulliez M.P.Y.,Heriot - Watt University | Cargill S.,Heriot - Watt University | McCracken S.,MCS Ltd
Electronics System Integration Technology Conference, ESTC 2010 - Proceedings | Year: 2010

New leak detection strategies are required for MEMS packages as traditional methods are not suited due to the small size of the cavities involved. This paper presents the design, fabrication and calibration procedure for three in-situ test structures intended to monitor electrically the hermeticity of packages. The calibration results of a micro-Pirani test structure show that this test structure can be used to monitor the ambient pressure of vacuum packaged MEMS. Using a pressured tracer gas to accelerate the test, the micro-Pirani test structure can detect leak rates down to 10-15 atm.cm3.s-1. Source

Mediware Alternate Care Solutions Inc., Carecentric National Llc and Mcs Inc. | Date: 2000-10-17

software program for use in processing transactions and creating and maintaining records and information within the home health industry.

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