S3-P3: Advanced no-field-plate AlGaN/GaN hemts for millimeter-wave MMIC applications

Abstract

We report successful development of an advanced no-field-plate AIGaN/GaN high electron mobility transistors (HEMTs) for millimeter-wave (MMW) applications. The HEMT adopts a reduced source-drain spacing of 2 J.1m and the 0.2-J.1m gate is placed 0.5 J.1m off the source electrode. Additionally, the devices and monolithic microwave integrated circuits (MMICs) are fabricated on the SiC substrate of 2mil, enabling the fabrication of 15 J.1m x 25 J.1m slot via holes for realizing low inductance and more compact devices to facilitate MMW MMIC design. As a result, the narrow band MMICs have achieved an output power of 10.4 W with associated power added efficiency (PAE) of 31% at 28 GHz, and 10.7W and 27% at 36 GHz, respectively. Besides, a state-of-the-art 2-stage single-ended wideband MMIC demonstrates output power of 5-7.9 Wand associated PAE of 13-21 % from low K-band to high Ka-band.

Trapping Phenomena in InAlN/GaN High Electron Mobility Transistors

“…The activation energy is low, as for process TP2d in Table I, and is attributed to capture of electrons by traps in the GaN buffer. 27 The barrier for capture in the TP1d process could be associated with 2DEG electrons being excited into the InAlN barrier over the conduction band offset between InAlN and GaN (about 1.1 eV [1][2][3][4]). These electrons are then captured by some states in the barrier (near the interface because the injected electrons have to travel uphill against the electric field in the barrier).…”

“…InAlN/GaN heterojunctions provide an alternative to AlGaN/GaN for use in high electron mobility transistors (HEMTs) with high power capability. [1][2][3][4][5][6][7][8] The advantages of InAlN/GaN heterojunctions compared to the AlGaN/GaN system include a very high spontaneous electrical polarization resulting in two-dimensional electron gas (2DEG) density of about 2.7 × 10 13 cm −2 , about twice as high as for AlGaN/GaN. [1][2][3][4][5][6][7][8] The InAlN barrier layer can be made closely lattice matched to GaN for In mole fraction of∼18%.…”

“…[1][2][3][4][5][6][7][8] The advantages of InAlN/GaN heterojunctions compared to the AlGaN/GaN system include a very high spontaneous electrical polarization resulting in two-dimensional electron gas (2DEG) density of about 2.7 × 10 13 cm −2 , about twice as high as for AlGaN/GaN. [1][2][3][4][5][6][7][8] The InAlN barrier layer can be made closely lattice matched to GaN for In mole fraction of∼18%. [1][2][3][4][5][6][7][8] The resulting decrease of strain and the absence of piezoelectric polarization should be beneficial for HEMTs' reliability and can potentially reduce current collapse phenomena in InAlN/GaN HEMTs.…”

“…[1][2][3][4][5][6][7][8] The InAlN barrier layer can be made closely lattice matched to GaN for In mole fraction of∼18%. [1][2][3][4][5][6][7][8] The resulting decrease of strain and the absence of piezoelectric polarization should be beneficial for HEMTs' reliability and can potentially reduce current collapse phenomena in InAlN/GaN HEMTs. 8,9 These advantages lead to superior device performance of InAlN/GaN HEMTs in some aspects to AlGaN/GaN HEMTs.…”

0.1-<inline-formula> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> Atomic Layer Deposition Al₂O₃ Passivated InAlN/GaN High Electron-Mobility Transistors for E-Band Power Amplifiers

“…In addition, a plasma enhanced chemical vapor deposition (PECVD) SiN was also introduced at later stage of the fabrication as the second passivation layer. The SiC substrate was thinned to 55 μm to enable the fabrication of 15 μm × 25 μm slot via holes, important for realizing low inductance and highly compact devices to facilitate MMW MMIC design [11].…”