Particle aggregation in the TZO thin films appeared to increase as the deposition power increased from 100 to 150 W, as shown in Figure 2b, c, d. This particle aggregation can be attributed to a high deposition rate due to the high-energy plasma when the deposition power was 125 and 150 W. However, as the deposition power was increased to 150 W, the roughness of the TZO thin films increased because of the large aggregations of particles. In Figure 2e, by contrast, the 100 W-deposited NiO thin film has a smooth and uniform

surface. Figure 2 Surface SEM images of TZO and NiO thin films as a NCT-501 research buy function of deposition power. TZO thin films were deposited at (a) 75 W, (b) 100 W, (c) 125 W, and (d) 150 W; (e) the NiO thin film Selleck Blasticidin S deposited at 100 W. NiO deposited at 100 W had a hall mobility

of 6.19 cm2/V s, carrier concentration of 4.38 × 1020 cm−3, and resistivity of 2.2 × 10–3 Ω cm (not shown here). Figure 3 shows the resistivity, hall mobility, and carrier concentration of the GDC-0068 ic50 TZO thin films as a function of deposition power. Electrons generated from oxygen vacancies and Zn interstitial atoms resulting from the dopant primarily determine the conduction properties of TZO thin films. Therefore, the films’ electrical conductivity will exhibit large variations when different deposition powers are used. As the deposition power was increased from 75 to 150 W, the hall mobility increased from 7.45 to 11.69 cm2/V s, and the carrier concentration increased from 2.75 × 1019 to 4.38 × 1020 cm−3. The higher hall mobility and carrier concentration are due to the higher deposition power; as it increases from 75 to 150 W, the kinetic energy of the deposited molecules Lck increases, so more molecules can diffuse and deposit onto the surfaces of the glass substrates. Consequently, the TZO thin films will have better crystal quality and larger particle aggregations. Therefore, a reduced grain boundary barrier is obtained, leading to an increase in carrier mobility. The resistivity of TCO thin films is proportional to the reciprocal of the product of carrier concentration (N) and hall mobility (μ): (1) which

is a combined result of both the mobility and the carrier concentration. The resistivity of TZO thin films linearly decreased from 1.3 × 10−2 to 2.2 × 10−3 Ω cm when the deposition power was increased from 75 to 150 W. Figure 3 Resistivity, hall mobility, and carrier concentration of TZO thin films as a function of deposition power. The surface SEM image of a heterojunction diode formed by using a 100 W-deposited NiO thin film on 125 W-deposited TZO thin film is shown in Figure 1a; the morphology was similar to that of the 125 W-deposited TZO thin film. Also, the surface morphologies of the 100 W-deposited NiO thin film on the 100 W-deposited and 150 W-deposited TZO thin films were similar to the results of the 100 W-deposited and 150 W-deposited TZO thin films (Figure 2b, d, not shown here).