Method for Reducing Mass Interference in Mass Spectroscopic Measurements
Original Publication Date: 1984-Feb-01
Included in the Prior Art Database: 2005-Feb-02
In mass spectroscopic analysis the detectability of a species of interest may be limited by a background signal of an entirely different species which happens to have the same mass. For example, a sputtering process often yields polyatomic fragments in addition to monatomic (or ions derived from monatomic) particles. An example is the sputtering of silicon and oxygen wherein a fraction of the sputtered material will be in the form of a silicon-oxygen cluster of the formula Si2O. A further fraction (0.03 x 0.046) of this will be 29Si 30SiO, which has a mass of 75. This mass interferes with the mass-spectroscopic analysis of arsenic, also of mass 75. Arsenic is often found in silicon semiconductors as a dopant.