2.2. Experimental Setup
Figure 1 shows the schematic diagram of the experimental setup. The p-type Bi0.45Sb1.55Te3 pellet was used as a target for laser ablation and mounted at the middle of the vacuum chamber with the surface make an angle 45 ̊ to the laser beam. One window of the vacuum chamber was mounted with ZnSe lens with a diameter of 10 mm. The ZnSe lens allowed the laser radiation from CO2 laser to pass into the vacuum chamber. The laser radiation was incident on the TE target surface and the heat from laser radiation ablated the TE target and deposited on the substrate. Si wafer with a dimension of 5 mm × 5 mm was used as the substrate. The distance between TE target and Si substrate was 2 cm.