Ge-Channel Thin-Film Transistor with Schottky Source/Drain Fabricated by Low-Temperature Processing

Abstract

The state-selective dissociation dynamics for anionic and excited neutral fragments of gaseous SiCl 4 following Cl 2p and Si 2p core-level excitations were characterized by combining measurements of the photoninduced anionic dissociation, x-ray absorption and UV/visible dispersed fluorescence. The transitions of core electrons to high Rydberg states/doubly excited states in the vicinity of both Si 2p and Cl 2p ionization thresholds of gaseous SiCl 4 lead to a remarkably enhanced production of anionic, Si − and Cl − , fragments and excited neutral atomic, Si * , fragments. This enhancement via core-level excitation near the ionization threshold of gaseous SiCl 4 is explained in terms of the contributions from the Auger decay of doubly excited states, shake-modified resonant Auger decay, or/and post-collision interaction. These complementary results provide insight into the state-selective anionic and excited neutral fragmentation of gaseous molecules via core-level excitation.

Growth and applications of GeSn-related group-IV semiconductor materials

“…In addition, the obtained mobility in this experiment is almost the same mobility (100–140 cm 2 V −1 s −1 ) as that for poly-Ge channel TFTs reported by Sadoh et al where the maximum process temperature was 500 °C in the SPC of a-Ge films [66, 67]. From these results, we can say that the 2% Sn incorporation into Ge can effectively improve the mobility, especially when low-temperature annealing is used; however, it is desirable to increase the hole mobility further because the mobility is still smaller than that of single-crystalline Si.…”

Dopant behavior in heavily doped polycrystalline Ge1−xSnxlayers prepared with pulsed laser annealing in water

“…Ge is one of the most attractive materials that meet the above requirements because it has a higher carrier mobility for both electrons and holes 1) and a lower polycrystallization temperature 2) than Si. From this background, many research groups have demonstrated the individual fabrication of p- [3][4][5][6] and n-type 7,8) polycrystalline Ge (poly-Ge) field-effect transistors (FETs) on insulating layers; in addition, poly-Ge CMOS operation has been achieved by Kamata et al 9) These studies are informative in the field of 3D-ICs. However, hightemperature lamp annealing above 840 °C is required for crystallizing an amorphous Ge (a-Ge) layer on SiO 2 ; also, annealing at a temperature as high as 600 °C is necessary for recrystallization and dopant activation after the ion implantation of n-type dopants.…”

(Invited) Single-Grain Germanium TFTs

“…In the TFTs using Ge channel, device has been fabricated with polycrystalline-Ge on a glass substrate. Because the film is polycrystalline, mobility becomes even lower by scattering at grain boundaries [3]. Off current becomes also very large due to carrier generation at the boundaries, resulting in very small on/off current ratio.…”