Analytical System for Measuring Water in a Gas Phase During Static Conditions
Original Publication Date: 1980-May-01
Included in the Prior Art Database: 2005-Feb-13
In sophisticated semiconductor packages having a hermetically enclosed volume filled with an inert gas phase, it is desirable to be able to check the concentration of water vapor in the enclosure as a check on the quality of the semiconductor package. Three problems are inherent when making water vapor concentration measurements of samples obtained from a small inaccessible volume, i.e., (1) the loss of water from the sample due to the strong, and usually variable, absorption of water on the surface of the transfer system, (2) unequal transfer of gasses in the sample to the sensing device due to small openings, and (3) non-linear or complicated sensing devices are usually needed for low PPM water concentration measurements.