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Achieving high-performance p-type semiconductors has been considered one of the most challenging tasks for three-dimensional vertically integrated nanoelectronics. Although many candidates have been presented to date, the facile and scalable realization of high-mobility p-channel field-effect transistors (FETs) is still elusive. Here, we report a high-performance p-channel tellurium (Te) FET fabricated through physical vapor deposition at room temperature. A growth route involving Te deposition by sputtering, oxidation and subsequent reduction to an elemental Te film through alumina encapsulation allows the resulting p-channel FET to exhibit a high field-effect mobility of 30.9 cm2 V−1 s−1 and an ION/OFF ratio of 5.8 × 105 with 4-inch wafer-scale integrity on a SiO2/Si substrate. Complementary metal-oxide semiconductor (CMOS) inverters using In-Ga-Zn-O and 4-nm-thick Te channels show a remarkably high gain of ~75.2 and great noise margins at small supply voltage of 3 V. We believe that this low-cost and high-performance Te layer can pave the way for future CMOS technology enabling monolithic three-dimensional integration.

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Copper(I) oxide (Cu 2 O), which is obtained from copper(II) oxide (CuO) through a reduction process, is a p-type oxide material with a band gap of 2.1−2.4 eV. However, the switching performance of typical Cu 2 O thin-film transistors (TFTs) is poor because the reduction process increases the concentration of oxygen vacancies (V O ), which interfere with the conduction of hole carriers. Ga with high oxygen affinity was doped in Cu 2 O thin films to decrease V O during the reduction process. As a result, the V O concentration of 1.56 at % for Ga-doped Cu 2 O (Ga:Cu 2 O) thin films decreased from 20.2 to 7.5% compared to pristine Cu 2 O thin films. Accordingly, the subthreshold swing or S-factor, on/off-current ratio (I on/off ), saturation mobility (μ sat ), and threshold voltage (V th ) of Ga:Cu 2 O TFTs were improved compared to pristine Cu 2 O TFTs with values of 7.72 from 12.50 V/dec, 1.22 × 10 4 from 2.74 × 10 2 , 0.74 from 0.46 cm 2 /Vs, and −4.56 from −8.06 V, respectively. These results indicate that Ga plays an important role in improving the switching performance of p-type Cu 2 O TFT.

We have implemented a 240Hz 55-inch ultra definition (UD, or 3840x2160) resolution TV panel using amorphous IGZO TFT. As the resolution and the frame rate of a panel increase, pixel charging time and panel transmittance ratio decrease. Among various data driving architectures, the data single 1G1D driving renders cost benefit, process competitiveness and design flexibility. To apply this driving architecture to a high resolution, high mobility of TFT and low RC delay are required. We suggest a-IGZO TFT and copper metallization technology as a solution.