Method for solvent-free perovskite deposition
A method for solvent-free perovskite deposition. The method comprises loading a lead target and one or more samples adhered to a substrate holder into a deposition chamber, pumping down to a high vacuum pressure, and backfilling the deposition chamber with the vapor of a salt precursor to form a perovskite material.
1. A method for solvent-free perovskite deposition comprising:
loading a lead target and a substrate into a deposition chamber;
reducing the pressure in the deposition chamber to less than or equal to 5×10 −6 Torr;
vaporizing the lead target;
backfilling, using a mass flow controller (MFC), the deposition chamber with the vapors of a salt precursor to form a thin film on the substrate, wherein the salt precursor comprises hydrogen iodide and wherein the backfilling occurs at a rate in a range of 2-100 sccm, and wherein the thin film comprises lead iodide;
transferring the thin film to a thermal evaporator; and
depositing a second salt precursor on the thin film to form a perovskite material on the substrate, wherein the second salt precursor selected from the group consisting of formamidinium iodide, methyl ammonium iodide, and combinations thereof.
2. The method of claim 1 , wherein the first 20 nm of depositions are made at a rate of 0.5 Å/second.
3. The method of claim 1 , wherein:
vaporizing occurs by applying an electron beam to the lead target.
4. The method of claim 1 , wherein:
vaporizing occurs by applying a cathodic arc to the lead target; and
the pressure in the chamber is reduced to the range of 10 −8 to 10 −12 Torr.
5. The method of claim 1 , wherein:
vaporizing occurs by applying a pulsed laser to the lead target; and
the pressure in the chamber is reduced to the range of 10 −8 to 10 −12 Torr.
6. The method of claim 1 , wherein the lead target consisting of lead (Pb).