Frustrated Lewis Pair Chelation as a Vehicle for Low-Temperature Semiconductor Element and Polymer Deposition

The stabilization of silicon(II) and germanium(II) dihydrides by an intramolecular Frustrated Lewis Pair (FLP) ligand, PB, (Pr2P)-Pr-i(C6H4)BCy2 (Cy=cyclohexyl) is reported. The resulting hydride complexes [PB{SiH2}] and [PB{GeH2}] are indefinitely stable at room temperature, yet can deposit films of silicon and germanium, respectively, upon mild thermolysis in solution. Hallmarks of this work include: 1) the ability to recycle the FLP phosphine-borane ligand (PB) after element deposition, and 2) the single-source precursor [PB{SiH2}] deposits Si films at a record low temperature from solution (110 degrees C). The dialkylsilicon(II) adduct [PB{SiMe2}] was also prepared, and shown to release poly(dimethylsilane) [SiMe2](n) upon heating. Overall, this study introduces a closed loop deposition strategy for semiconductors that steers materials science away from the use of harsh reagents or high temperatures.

Automated summary

This study presents a method to stabilize silicon(II) and germanium(II) dihydrides using an intramolecular Frustrated Lewis Pair (FLP) ligand, PB. The resulting hydride complexes are indefinitely stable at room temperature and can deposit silicon and germanium films upon mild thermolysis. Overall, this work introduces a closed-loop deposition strategy for semiconductors, reducing the reliance on harsh reagents or high temperatures.