Amorphous films of Cd1-xPbxI2 solid solutions and their crystallization studied by simultaneous measurements of UV absorption and reflection

Amorphous films (thickness in the range 300 to 600 nm) of Cd1-xPbxI2 solid solutions are obtained by quench-deposition onto 77 K substrates. Upon slow heating (approximate to 0.4 K min(-1)), they crystallized in a narrow temperature range, exhibiting a well-defined crystallization temperature over the whole range of x. The crystallization temperature decreases with increasing x, from approximate to 300 K for x = 0 to 197 K for x = 1. For small x (<0.1) Pb atoms provide nucleation centers with low activation barriers.