Si Ion Implantation into Mg-Doped GaN for Fabrication of Reduced Surface Field Metal–Oxide–Semiconductor Field-Effect Transistors

Abstract

We have studied the activation of Si ion implanted un-and Mg-doped gallium nitride (GaN) for the fabrication of reduced surface field (RESURF) metal-oxide-semiconductor field-effect transistors (MOSFETs). By annealing at 1260 C for 30 s by using rapid thermal annealing (RTA), the activation ratios of un-and Mg-doped GaN with Si doses of 3 Â 10 15 cm À2 were $100 and 73%, respectively. These values are sufficient for application some semiconductor devices. Hardly any diffusion of the Si atoms implanted in GaN was observed by secondary ion mass spectrometry (SIMS). The activation ratio between unand Mg-doped GaN was markedly different at low doses. The cause of the difference appears to be Mg compensation in GaN. In addition, we fabricated GaN MOSFETs with ion implanted RESURF zones. We also monitored the field-effect transitor (FET) operation and high breakdown voltage of the GaN MOSFETs. The threshold voltage was +2 V. An enhancement mode operation and a breakdown voltage higher 1500 V at a RESURF length of 20 mm were achieved.

Over 1000V/30mA operation GaN-on-Si MOSFETs fabricated on Si substrates

“…We have studied Si ion implantation into Mg-doped GaN ([Mg] = 1 Â 10 17 cm À3 ) grown on Si substrates [10,[16][17][18][19][20].…”

“…We previously fabricated the GaN MOSFETs on the sapphire substrate by using the ion implantation which has advantages of selective and uniformity doping techniques [9][10][11][12]. By introducing the reduced surface field (RESURF) structures, we achieved 1550 V/ 2 A operation on the GaN MOSFETs on the sapphire substrates.…”

An over 100 W AlGaN/GaN enhancement‐mode HEMT power amplifier with piezoelectric‐induced cap structure

“…[11] [6] [13] [18] [21] Furthermore, the GaN E-mode HEMT amplifier is embedded in the digital pre-distortion (DPD) system, which was developed for practical mobile WiMAX base station amplifiers. The measurement conditions were V d of 50 V, V g of around 0 V, quiescent current (I dsq ) of 280 mA and signal width of 20 MHz.…”

“…Recently, E-mode RF devices have been required for simplifying power amplifier circuits using a single-polarity voltage supply, fail-safe operation, improving distortion [3] and ensuring compatibility with existing systems. Recently, E-mode operated GaN-based HEMTs have been reported using gate recess [4][5][6][7][8][9], fluoride-based plasma treatment [10][11][12][13][14], InGaN cap layer [15], p-(Al)GaN cap layer [16,17], MOS structure [18][19][20], thin electron supply layer [21,22] and non-polar surface [23]. The recessed gate structure has been researched because of its simple and low-damage process.…”

Quadrupole SIMS Analysis of Si Concentration in GaN Layers by a Molecular Ion Detection with a Minor Isotope

“…Donor doping with Si is the most common method for achieving n-type conducting GaN. Since the control of carrier concentration in n-type GaN layers is very important for off-state breakdown voltage and on-state resistance characteristics, the quantitative analysis of Si concentration in n-type ohmic contact and reduced surface field (RESURF) GaN layers by secondary ion mass spectrometry (SIMS) measurements is required [7]. Generally, a magnetic sector SIMS instrument is capable of a lower detection limit and higher mass resolving power, whereas a quadrupole SIMS (Q-SIMS) instrument provides better depth resolution for thin film measurement.…”