Nearly Perfect Electrical Activation Efficiencies from Silicon-Implanted Al x Ga1−x N with High Aluminum Mole Fraction

Abstract

Electrical activation studies of Al x Ga 1-x N (x = 0.45 and 0.51) implanted with Si for n-type conductivity have been made as a function of ion dose and anneal temperature. Silicon ions were implanted at 200 keV with doses ranging from 1 9 10 14 cm -2 to 1 9 10 15 cm -2 at room temperature. The samples were subsequently annealed from 1150°C to 1350°C for 20 min in a nitrogen environment. Nearly 100% electrical activation efficiency was successfully obtained for the Si-implanted Al 0.45 Ga 0.55 N samples after annealing at 1350°C for doses of 1 9 10 14 cm -2 and 5 9 10 14 cm -2 and at 1200°C for a dose of 1 9 10 15 cm -2 , and for the Al 0.51 Ga 0.49 N implanted with silicon doses of 1 9 10 14 cm -2 and 5 9 10 14 cm -2 after annealing at 1300°C. The highest room-temperature mobility obtained was 61 cm 2 /V s and 55 cm 2 /V s for the low-dose implanted Al 0.45 Ga 0.55 N and Al 0.51 Ga 0.49 N, respectively, after annealing at 1350°C for 20 min. These results show unprecedented activation efficiencies for Al x Ga 1-x N with high Al mole fractions and provide suitable annealing conditions for Al x Ga 1-x N-based device applications.

AlN metal–semiconductor field-effect transistors using Si-ion implantation

“…High-dose and highenergy ions have been used in the past in III-N semiconductors to obtain a high carrier concentration at somehundred-nm depth. [18][19][20] This high-dose and high-energy ion implantation significantly damages the crystal lattice and introduces a high concentration of point defects, resulting in carrier compensation. Thermal annealing is helpful to heal the ion-implantation damage, although very high temperatures are typically required in wide band-gap semiconductors (e.g., 900-1000 °C for Ga 2 O 3 , 21) 1000-1400 °C for AlGaN, [18][19][20]22) and 1400-1700 °C for SiC 23) ) due to the high thermal stability of point defects.…”

“…[18][19][20] This high-dose and high-energy ion implantation significantly damages the crystal lattice and introduces a high concentration of point defects, resulting in carrier compensation. Thermal annealing is helpful to heal the ion-implantation damage, although very high temperatures are typically required in wide band-gap semiconductors (e.g., 900-1000 °C for Ga 2 O 3 , 21) 1000-1400 °C for AlGaN, [18][19][20]22) and 1400-1700 °C for SiC 23) ) due to the high thermal stability of point defects. The Si-ion implantation damage in AlN can be healed by annealing for 1230-1600 °C in a nitrogen ambient, showing n-type conductance.…”

Electrical Activation Studies of Silicon-Implanted Al x Ga1−x N with Aluminum Mole Fraction of 11% to 51%

“…Recently, our group achieved nearly perfect electrical activation efficiencies from Si-implanted Al x Ga 1Àx N with an Al mole fraction more than 30%. 11,12 In the present paper, electrical activation studies of Si-implanted Al x Ga 1Àx N at 200 keV with doses ranging from 1 9 10 14 cm À2 to 1 9 10 15 cm À2 are reported as a function of ion dose and annealing temperature for Al mole fractions from 11% to 51%.…”