Thermal Decomposition of Copper Iminopyrrolidinate Atomic Layer Deposition (ALD) Precursors on Silicon Oxide Surfaces
The thermal chemistry of Cu(I)-N-sec-butyl-iminopyrrolidinate on silicon oxide films was characterized by using temperature-programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS). Three temperature regimes were identified after adsorption at 100 K: (1) molecular desorption at 240 K; (2) protonation of some of the ligands and formation of the corresponding iminopyrrolidine at 300 K; and (3) fragmentation of the remaining ligands to produce H2, HCN, and butene, which occurs concurrently with the reduction of the copper ions. Most of the carbon and nitrogen atoms are removed from the surface after the third step, and copper desorbs above 900 K. Adsorption of the copper complex at room temperature leads to a partial early reduction of the metal and to the extended production of sec-butyl-iminopyrrolidine in two broad peaks around 330 and 460 K. Self-limiting adsorption, as required for atomic layer deposition (ALD) processes, is seen up to 500 K, but by 550 K continuous copper deposition takes place. In general, the chemistry of this copper ALD precursor is milder and cleaner on silicon oxide than on metals.
|Journal||The Journal of Physical Chemistry Part C|
Yao, Y. (Yunxi), Coyle, J.P, Barry, S.T, & Zaera, F. (Francisco). (2016). Thermal Decomposition of Copper Iminopyrrolidinate Atomic Layer Deposition (ALD) Precursors on Silicon Oxide Surfaces. The Journal of Physical Chemistry Part C, 120(26), 14149–14156. doi:10.1021/acs.jpcc.6b03818