Effect of substrate temperature on the characterization of molybdenum contacts deposited by DC magnetron sputtering

This study involved depositing back contacts of molybdenum (Mo) thin film for Cu (In,Ga)Se ₂ (CIGS) solar cells on soda-lime glass substrates via DC magnetron sputtering, investigating the microstructural, mechanical, and optoelectronic properties of the deposited Mo films as a function of the substrate temperature T _sub. The experimental results show that the interface adhesion strength between the glass substrate and the Mo film increases in conjunction with T _sub. The best adhesion strength was obtained at over 25 MPa, and the root mean square of the surface roughness has the lowest value of 1.0 nm. The Mo contacts deposited at T _sub over 200 °C had an average optical reflectivity as high as 57.4% within the wavelength range from 400 nm to 1200 nm. When T _sub equals 250 °C under a working pressure of 0.39 Pa, the Mo film has the lowest resistivity of 1.1 × 10-5 Ω·cm.