## 3 Results and Discussion
These results are consistent with those of previous  
Figure 1:0 Comparisons of (**a**) transfer and (**b**) output characteristics of MoS\({}_{2}\) TFTs with respect to Al\({}_{2}\)O\({}_{3}\) passivation. Variations of (**c**) field-effect mobility (\(\mu_{\rm eff}\)) and (**d**) threshold voltage (\(\Delta V_{\rm th}\)) of \(15\) representative Al\({}_{2}\)O\({}_{3}\)-passivated MoS\({}_{2}\) TFTs compared with those of pristine devices. All the Al\({}_{2}\)O\({}_{3}\) layers were deposited after UV-ozone treatment. reports on Al\({}_{2}\)O\({}_{3}\)-encapsulated MoS\({}_{2}\) devices, which indicates that no significant defect was introduced in the MoS\({}_{2}\) by the UV-ozone treatment [27; 28]. The MoS\({}_{2}\) surface before and after UV-ozone treatment were investigated using Raman and X-ray photoelectron spectroscopy (shown in Figure S2). Figure 3c,d show the statistical distributions of \(\mu_{\text{eff}}\) and \(\Delta V_{\text{th}}\) for 15 representative MoS\({}_{2}\) TFTs in order to confirm the effect of UV-ozone pre-treatment followed by Al\({}_{2}\)O\({}_{3}\) passivation. The results of all the devices exhibit increments of the \(\mu_{\text{eff}}\) as well as reduction of the \(\Delta V_{\text{th}}\). The average increment (reduction) rate of \(\mu_{\text{eff}}\) (\(\Delta V_{\text{th}}\)) is 40.4% (4.2%). The individual values of \(\mu_{\text{eff}}\) and \(\Delta V_{\text{th}}\) are listed in Figure 1:1 These results are evidence that UV-ozone treatment of the multilayer MoS\({}_{2}\) TFTs not only improves the quality of the ALD-grown Al\({}_{2}\)O\({}_{3}\) layer, but also enhances the mobility and stability of the MoS\({}_{2}\) devices. To demonstrate the temperature-dependent behavior of the Al\({}_{2}\)O\({}_{3}\)-passivated MoS\({}_{2}\) TFT, the electrical properties of the device were measured at 10 different temperatures ranging from 293 K to 380 K under a moderate vacuum condition. Figure 4a presents a semi-logarithmic-scale plot of the temperature-dependent transfer characteristic curves at five different temperatures (293, 310, 330, 350 and 370 K). At the semi-logarithmic-scale of \(I_{\text{ds}}\), variation of \(I_{\text{on}}\) was not clearly distinguished. To reveal the enhancement of \(I_{\text{on}}\), linear scale plots of the transfer curves at five other temperatures (300, 320, 340, 360 and 380 K) are compared in Figure 4b. As shown in Figure 4, \(I_{\text{ds}}\) increased with increasing temperature over the whole \(V_{\text{gs}}\) region. The results also confirmed the linear increment of the \(I_{\text{ds}}\) values at a \(V_{\text{gs}}\) of 40 V with respect to 10 different temperatures, as shown in the inset of Figure 4a. From the transfer characteristic curves, we extracted the \(V_{\text{th}}\) at 10 different temperatures, which linearly shifted toward the negative \(V_{\text{gs}}\) region with increasing temperature (inset of Figure 4b). Figure 5a shows the output characteristics of the Al\({}_{2}\)O\({}_{3}\)-passivated MoS\({}_{2}\) TFT at 293 K with those at 380 K, which exhibits almost double increments of \(I_{\text{ds}}\). The results also imply that high temperature would influence the other aspects of TFT performance. However, our TFT architecture has a two-terminal configuration resulting in contact resistance between the S/D electrodes and the MoS\({}_{2}\) active channel, which should be minimized for further investigation of carrier transport mechanisms.