**Figure 5.**

*Current–voltage (I-V) characteristics of (a) bare Si(111) substrate, (b) as grown SiC on Si(111), 80 keV argonsputtered SiC surface for fluence of (c) 5 × 1017 Ar+ cm−2 and (d) 7 × 1017 Ar+ cm−2.*

The current passing through the films exhibited a noticeable reduction transitioning from (a) Si(111) to (b) SiC thin film and then with increase in argon ion fluence (c) and (d). This decrease in current exhibited a linear relationship graphically represented in **Figure 5**. The linear correlation between the applied voltage and the resulting current indicates that the as-deposited and argon-sputtered SiC thin films exhibit ohmic behavior within the designated voltage range of −5 to 5 V.

Moreover, the resistivity of the thin films can be determined by the equation [20–21]:

$$
\rho = R \frac{A}{l} \tag{1}
$$

In this equation, ρ represents the resistivity, *R* stands for the resistance, *A* denotes the surface area of the SiC thin films, and *l* represents the distance between the two measurement probes.

*Oblique Ar+ Sputtered SiC Thin Films: Structural, Optical, and Electrical Properties DOI: http://dx.doi.org/10.5772/intechopen.112928*

**Figure 6.** *Variation of conductivity of SiC thin films with Ar+ ion fluence.*

Interestingly, using these values of resistivity, conductivity can be calculated as

$$
\sigma = \frac{1}{\rho} \tag{2}
$$

Here, σ signifies the conductivity of the thin films and ρ corresponds to the resistivity of the SiC films. **Figure 6** represents the variation of conductivity as a function of argon ion fluence.

Interestingly, the conductivity of thin SiC thin films was found to decrease with increasing argon ion fluence. The increase in resistivity and decrease in conductivity of SiC thin films with increasing ion fluence can be attributed to the introduction of defects and disruptions in the crystal lattice. The ion beam bombardment leads to the creation of vacancies, interstitials, and lattice distortions in the SiC thin films. These defects act as scattering centers for charge carriers (electrons or holes), hindering their mobility and thereby increasing resistivity. The mobility of charge carriers is reduced due to an increase in scattering leads to a decrease in the conductivity of SiC thin films. In the case of the Si(111) wafer, the observed highest conductivity could be due to its single-crystalline structure and minimal defect density compared to the irradiated SiC thin films [22].

The increase in the optical band gap value with ion fluence suggests that the material's electronic structure is being modified. The ion bombardment can induce changes in the electronic states of the material, including the creation of localized energy levels within the band gap. These levels can trap charge carriers, reducing their mobility and contributing to a decrease in conductivity.
