Molybdenum film for photovoltaic cells

How are molybdenum films deposited?

Molybdenum (Mo) films were deposited by radio frequency (RF), direct current (DC) and mixed magnetron sputtering, respectively. With changing the deposition parameters including deposition pressure and power, the films show different surface morphology and crystallinity.

Which molybdenum film has the lowest resistivity?

The lowest resistivity of Mo films is 34×10 -6 Ω ·cm with the deposition pressure of 0.1 Pa, but it is failed in the adhesion test. The bilayer molybdenum films and tri-layer molybdenum films all show good adhesion and low resistivity.

Is molybdenum oxide a hole-selective contact layer?

Molybdenum oxide (MoO X, X < 3) has received special interests as a hole-selective contact layer in a variety of solar cells [1, 2, 3, 4, 5, 6] because of its wide bandgap (~ 3 eV), excellent low absorption as a window layer ,and exceptionally large work function (~ 6.7 eV).

Is Mo metal a good back contact material for CIGS solar cells?

The comparison of Mo metal and other materials indicate Mo is an ideal back contact material for CIGS solar cells, because of its inertness and high conductivity. 7 However, it is difficult to obtain the low resistivity and the good adhesion simultaneously.

What is the lowest resistivity of a single Mo film?

The lowest resistivity of the single Mo film is 34×10 -6 Ω ·cm when the deposition pressure is 0.1 Pa and the deposition power is 300 W in the DC mode. In order to obtain lower resistivity, better adhesion and better reflectivity, bilayer films and tri-layer films were both deposited in different mode.

How does deposition pressure affect the crystallinity of Mo Films?

The crystallinity of Mo films is inversely proportional to the deposition pressure. The Mo films have a small, densely packed grain microstructure at low deposition pressure of 0.1 Pa and the surface of the Mo films deposited at 0.3 and 0.6 Pa shows loose and elongated grains.