Zinc bis(2,2,6,6-tetramethylpiperidide) Zn(tmp)2 is a volatile solid subliming at temperature 75-80°C / 0.01 Torr (older data 135°C/ 0.01 Torr). It is synthesized by the reaction of anhydrous ZnCl2 and 2 equivalents of lithium 2,2,6,6-tetramethylpiperidide in ~60% yield and purified by crystallization from cold hexane solution (35°C). It is an air sensitive compound, but not pyrophoric - the advantage over zinc dialkyls for MOCVD practice.+
[S. Suh, L. A. Mîinea, D. M. Hoffman, Z. Zhang, W.-K. Chu, J. Mater. Sci. Letters, Volume 20, Number 2, 115-118, DOI: 10.1023/A:1006777915520]
Zn(tmp)2 has been applied as precursor for the growth of undoped zinc oxide films by atmospheric pressure CVD at 250-400°C growth temperatures (using extra dry O2 as oxidant). Growth rates 4-9 nm/min were obtained at 250-350°C growth temperature (with precursor evaporated at 70°C, growth rates increased to 17nm/min after increase of precursor evaporation temperature to 85°C). Film stoichiometry was changing to lower oxygen content from ZnO1.2-0.9 growth temperature from 250°C to 400°C; resistivity of the layers grown at 400°C was 75-80 Ohm*cm.
[S. Suh, L. A. Mîinea, D. M. Hoffman, Z. Zhang, W.-K. Chu, J. Mater. Sci. Letters, Volume 20, Number 2, 115-118, DOI: 10.1023/A:1006777915520]]