**2. Experimental**

In this study, experiment is held under thermal vapor deposition technique using single-stage horizontal glass tube furnace. In this experiment, 99.9% pure magnesium, Zinc, and Copper powders along with Ge, In, and Al powders are used under the ratio 1:1 as source material. This source material is being kept in the center of a glass tube in ceramic boat. The silicon substrate is placed at substrate holder, and the distance between source and the substrate is about 15 cm. The temperature of the furnace is tuned at 950°C for 30 min, whereas the oxygen flow is kept constant at 100 sccm. After the growth of thin film, the substrate of silicon is divided into different pieces for annealing purpose at different temperatures from 600 to 800°C for 30 min.

X-ray diffraction has been performed for the structural analysis of grown thin film. Raman spectroscopy has been also performed to study the rotational and vibrational modes of thin film. Surface morphology is being assessed by the scanning electron microscope (SEM). The most important characterization to calculate

**53**

**Figure 3.**

*Thermoelectric Properties of Oxide Semiconductors DOI: http://dx.doi.org/10.5772/intechopen.88709*

**3. Results and discussion**

(006) at 2θ = 33.086°

sured by the filmtronics technique and it is about.

The diffraction peak at 25.8, 42.9, 44.7, 58.4, 58.9, and 65°

*(a–c) XRD patterns of Cu2InO4, CuAlO2, and Zn2GeO4, respectively.*

Seebeck coefficient has been performed on the homemade Seebeck system which is based on the four-probe system. And the thickness of the thin film has been mea-

**Figure 3**(**a–c**) represents the XRD patterns of Cu2InO4, CuAlO2, and Zn2GeO4 thin films annealed at different temperature from 600 to 800°C, respectively. The XRD graph of Cu2InO4 thin films in **Figure 3**(**a**) demonstrated that unannealed and low temperature (600°C) would not be able to make the grown material crystalline due to low thermal energy for bonding. But as we increased the temperature above 600°C, the sample is converted into crystalline structure with preferred orientation

increased as we further increase the annealing temperature, which suggested that carriers now get enough energy to sit down at a particular position in planes of the crystal. **Figure 3**(**b**) shows the XRD graph of CuAlO2. The unannealed sample consists of one major phase at 2θ = 32.05 which belongs to CuAlO2 (0 0 6) plane [13]. Annealing resulted in the development of new phases at 2θ = 35.4, 42.4, and 48.4 related to CuO (1 1 1) and CuAlO2 (1 0 4) and (0 0 9) orientations, respectively. We have observed that (0 0 6) plane has the strongest intensity which is oxygen sensitive; therefore, enhancement of intensity of this plane with annealing temperature is understandable. **Figure 3**(**c**) shows the XRD pattern of grown and annealed samples of Zn2GeO4 thin films at various temperatures. The unannealed and annealed samples consist of eight diffraction peaks which are related to Zn2GeO4, Si, Au, and ZnO, respectively.

[11, 12]. It is also observed that the intensity of this plane is

are belonging to Zn2GeO4

Seebeck coefficient has been performed on the homemade Seebeck system which is based on the four-probe system. And the thickness of the thin film has been measured by the filmtronics technique and it is about.
