Liquid injection field desorption/ionization as a powerful tool to characterize volatile, labile, and reactive metal–organic complexes

Abstract

Electron ionization mass spectrometry (EI-MS) is often used to characterize volatile and thermally stable organometallic complexes relevant for chemical vapor deposition (CVD) processes. However, this method has limitations for thermally unstable and labile organometallic complexes. In this context, EI-MS is not the preferred method of choice for characterizing such compounds. With three different representative organometallic complexes based on the transition metals yttrium, iridium, and silver, relevant as precursors for CVD of different materials, the significance of liquid injection field desorption/ionization mass spectrometry (LIFDI-MS) as an important precursor characterization tool is exemplified. The precursors are not only reactive toward ambient air, but also thermally labile especially in the case of iridium and silver complexes. As a promising alternative, LIFDI-MS is used to overcome the limitations of EI-MS. For the first time, these complexes were successfully analyzed using LIFDI-MS. The comparison between EI-MS and LIFDI-MS highlights that LIFDI-MS is superior for the mass spectrometric analysis of sensitive and labile complexes. In terms of precursor characterization, LIFDI-MS can be fully exploited to gain valuable insights into the decomposition mechanisms and identifying the nuclearity of organometallic precursors used for CVD applications.

In Pursuit of Next Generation N-Heterocyclic Carbene-Stabilized Copper and Silver Precursors for Metalorganic Chemical Vapor Deposition and Atomic Layer Deposition Processes

“…This, indeed, once more confirms the distinctive bonding of the NacacMe ligand in [Ag(tBuNHC) (NacacMe)]. Furthermore, the nature of the synthesized complexes is confirmed via mass spectrometry (FiguresS11-S13), specifically using LIFDI-MS (liquid injection field desorption ionization mass spectrometry), for which we previously reported its advantage in using highly unstable and reactive organometallic complexes[49].…”

“…In comparison with each other, particularly in the fingerprint region (<1500 cm S13), specifically using LIFDI-MS (liquid injection field desorption ionization mass spectrometry), for which we previously reported its advantage in using highly unstable and reactive organometallic complexes [49].…”