Effects Of Dopants on the Electrical Transport Properties of Czochralski (CZ) and Edge-Defined Film-FED (EFG) Growth Grown $\beta $\textbf{-GA}$_{\mathrm{\mathbf{2}}}$\textbf{O}$_{\mathrm{\mathbf{3}}}$

Gallium oxide (Ga$_{\mathrm{2}}$O$_{\mathrm{3}})$ is the widest band gap (4.8-5.0 eV) semiconducting oxide known so far transparent up to UV-C range. Due to wide band gap and high Baliga's Figure of Merit (FOM), it possesses excellent material properties for high power device applications. It exists in five different polymorphs ($\alpha $, $\beta $, $\gamma $, $\delta $ and ), with $\beta $ being the most stable at all temperatures. Electrical transport properties of Czochralski (CZ) grown and Edge-Defined Film-Fed Growth (EFG) grown samples were evaluated by using Hall effect and Van der Pauw techniques. The conductivity of samples was found to be highly dependent on doping material. Un-doped $\beta $-Ga$_{\mathrm{2}}$O$_{\mathrm{3}}$ single crystal is highly resistive ( 10$^{\mathrm{7\thinspace }}\Omega $.cm), but the Sn-doped $\beta $-Ga$_{\mathrm{2}}$O$_{\mathrm{3}}$ has significantly lower resistivity. The resistivity of Mg-doped and Fe-doped samples were relatively higher than the un-doped samples. Positron annihilation measurements were conducted to investigate the effect of compensating defects on conductivity.