Ti-based nonalloyed Ohmic contacts for Al0.15Ga0.85N∕GaN high electron mobility transistors using regrown n+-GaN by plasma assisted molecular beam epitaxy

Abstract

Development of high-performance fully depleted silicon-on-insulator based extended-gate field-effect transistor using the parasitic bipolar junction transistor effect Appl. Phys. Lett. 101, 133703 (2012) Abnormal interface state generation under positive bias stress in TiN/HfO2 p-channel metal-oxide-semiconductor field effect transistors Appl. Phys. Lett. 101, 133505 (2012) Top-gate staggered poly(3,3″′-dialkyl-quarterthiophene) organic thin-film transistors with reverse-offset-printed silver source/drain electrodes Appl. Phys. Lett. 101, 133306 (2012) Subthreshold swings below 60mV/dec in three-terminal nanojunctions at room temperature Appl. Phys. Lett. 101, 133504 (2012) Top-gate staggered poly(3,3″′-dialkyl-quarterthiophene) organic thin-film transistors with reverse-offset-printed silver source/drain electrodes APL: Org. Electron. Photonics 5, 220 (2012) Additional information on Appl. Phys. Lett.

Improvement of Au‐Free, Ti/Al/W Ohmic Contact on AlGaN/GaN Heterostructure Featuring a Thin‐Ti Layer and Low Temperature Annealing

“…We can also infer that the minimum annealing temperature is approximately 500 °C. This is consistent with studies on low temperature annealed ohmic contact on GaN, in which the optimal temperature is often 500 °C or more, except for non‐alloy techniques such as the ones that use heavily doped GaN . The data on Ti/Al‐based scheme with recessed contacts do not necessarily follow the linear relationship as shown in Figure , meaning that the current flows by another conduction mechanism, such as direct contact with 2DEG.…”

“…Therefore, lowering the annealing temperature is another challenge in ohmic contacts. One of the ways to realize low‐temperature‐annealed Au‐free ohmic contacts is using pre‐metal‐deposition treatments, such as recess etching under ohmic contact and regrown n + ‐GaN . However, these techniques increase the number of steps in the fabrication process of HEMTs, thus increasing the costs and causing a high level of defectiveness.…”

Breakdown Voltage Enhancement of AlGaN/GaN High-Electron-Mobility Transistors via Selective-Area Growth for Ohmic Contacts over Ion Implantation

“…In our previous studies, we were able to realize SAG with PAMBE, achieving a record low contact resistivity of 1.8 9 10 À8 X cm 2 for Ohmic contacts to an n-type GaN channel of a metalÀsemiconductor field-effect transistor (MESFET) 9 and an extremely low nonalloyed contact resistance of 0.6 X mm for contacts to a two-dimensional electron gas (2DEG) channel in an AlGaN/GaN high-electron-mobility transistor (HEMT). 10 These results not only demonstrate the advantage of SAG over the conventional contact scheme, but also indicate that SAG may be a better choice than ion implantation for fabricating Ohmic contacts. Furthermore, due to the damage-free nature of the SAG technique, we infer that it would provide higher breakdown voltage than ion implantation, which is crucial for high-power GaN devices.…”

High‐current AlGaN/GaN high electron mobility transistors achieved by selective‐area growth via plasma‐assisted molecular beam epitaxy

“…In our previous studies, we were able to realize SAG by PAMBE, achieving a record low contact resistivity of 1.8 × 10 −8 Ω cm 2 and much enhanced peak drain currents for both GaN MESFET and HEMT . We also demonstrated that unlike ion implantation, the damage‐free PAMBE‐SAG technique is able to suppress the buffer leakage current and improve the breakdown characteristics .…”