Current annealing to improve drain output performance of β-Ga2O3 field-effect transistor

Effects of Annealing on Surface Residual Impurities and Intrinsic Defects of β-Ga2O3

“…The average FWHM of the (201) diffraction peak was 44.2 arcsec for the pristine sample, which reduced to the average value of 38.3 arcsec due to vacuum annealing. The reduced FWHM indicates an improvement in bulk crystallinity, and the resultant dislocation density decreased from 3.1 × 10 4 to 2.3 × 10 4 cm −3 as extracted from the FWHMs [20,21]. However, although the FWHM of the O 2 -annealed sample (44.6 arcsec) was similar to that of the control sample, an obvious shoulder peak appeared (Figure 1b: red line), which was attributed to the strain accumulation induced by the diffusion of Si and Cr impurities toward the surface (detailed discussion provided in the SIMS section).…”

“…Although the defects of V 0 O(III) are located at 1.7 eV below the conduction band, which corresponds to a wavelength of around 716 nm [11], it should not be the origin of the red PL peak because V O is difficult to form in oxygen ambience due to its high formation energy of 4.7 eV [10,11]. Furthermore, the broad red PL peak can be attributed to the electron transitions from the 4 T 2 and 2 E states to the 4 A 2 levels of the Cr 3+ impurities [28][29][30][31][32], which are generated by recharging Cr 2+ during thermal annealing to shift the Fermi level away from the conduction band [21,22]. As for the spike peak at 690 nm, the transition of the 2 E:R 2 states to ground 4 A 2 is believed to be the dominant origin [18,33,34].…”

Structural and optoelectronic characteristics of β-Ga2O3 epitaxial films with Zn alloying and subsequent oxygen annealing

“…Furthermore, steep absorption edges can be clearly observed at B255 nm. According to the plots of (ahn) 2 versus hn in the inset of Fig. 1c, the optical bandgap (E g ) of pure b-Ga 2 O 3 , b-Ga 2 O 3 :Zn, annealed b-Ga 2 O 3 and annealed b-Ga 2 O 3 :Zn can be evaluated to be 5.23, 5.21, 5.19, and 5.15 eV, respectively.…”

“…Ultra-wide bandgap gallium oxide (Ga 2 O 3 ), with remarkable thermal and chemical stability, is suitable for many promising areas of applications, such as solar-blind photodetectors, gas sensors, solar cells, power electronic devices, and so on. [1][2][3][4][5][6][7] There are six different crystalline structures of Ga 2 O 3 , including a-, b-, g-, d-, eand k-Ga 2 O 3 . [8][9][10] In comparison, the most stable phase among them is monoclinic b-Ga 2 O 3 with a direct bandgap of B4.9 eV.…”

Vacuum Inner Spacer to Improve Annealing Effect during Electro-Thermal Annealing of Nanosheet FETs

“…The ETA effectively cures the gate dielectric damage produced by hot-carrier injection (HCI), bias-temperature instability (BTI), and even total ionizing dose (TID). In addition, the ETA is applicable for removing contaminants such as photoresist (PR), moisture, or traps existing in channels [ 9 , 10 ]. However, additional power consumption is inevitably required to trigger the ETA.…”