Krypton and Xenon in Semiconductors

Krypton and xenon are produced from the air. Krypton is naturally present in the air at a concentration of 1 ppm and xenon is present at a concentration of 87 ppb. Both are collected as secondary products of cryogenic air separation at air separation units (ASUs). ASUs separate the components of air based on their boiling points using cryogenic distillation. This is the common method of production for oxygen, nitrogen, argon, as well as rare gases neon, krypton, and xenon. There are many ASUs around the globe. The ability to produce krypton and xenon is not inherently part of the process as it requires additional equipment beyond that required to collect oxygen or nitrogen. The krypton and xenon price when an ASU is planned and built determines if the capability to collect these gases is added.