Effects of sputtering power on properties of PbSe nanocrystalline thin films deposited by RF magnetron sputtering

• Nanocrystalline PbSe films were deposited by RF magnetron sputtering for the first time.
• The crystalline grains are spherical under low power, which are cubic-shaped under higher power.
• The optical band gap values for PbSe films depend on grain size rather than on film thickness.

PbSe nanocrystalline films were prepared by radio frequency (RF) magnetron sputtering with different powers ranging from 40 to 100 W. The impact of RF power on the crystal structure, surface morphology, and optical properties of the as-deposited films were investigated. Results show that the film demonstrates typical preferred orientation in (200) orientation. And the intensity for all diffraction peaks is enhanced with increasing sputtering power. The grains are equiaxial sphere under lower power, which turns to regular cubic-shaped ones under higher power. The calculated optical band gap of the films lies between 1.26 and 2.02 eV. This broader band gap suggests an important potential application in solar cells.