Asymmetrical Contact Geometry to Reduce Forward-Bias Degradation in β-Ga<sub>2</sub>O<sub>3</sub> Rectifiers

Xian, Minghan; Fares, Chaker; Ren, F.; Haque, Aman; Tadjer, Marko J.; Pearton, S. J.

doi:10.1149/2162-8777/ab7b44

Cited by 12 publications

(14 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Xian et al fabricated vertical Ni/β-Ga 2 O 3 SBDs on HVPE grown (001) oriented epilayers. They studied forward bias degradation and thermal failures under high current density operation. , They found that forward-bias stress caused reverse breakdown degradation and thermally induced failure on both the SC and the epilayer due to the low thermal conductivity of Ga 2 O 3 . The simulation of temperature distributions at forward bias under different current conditions revealed that maximum temperature rise (270–350 °C) occurs at the MS contact center .…”

Section: Schottky Contacts To Ga2o3mentioning

confidence: 99%

“…The maximum current density achievable with each orientation is mentioned in each diode. Reproduced with permission from ref . Licensed under a Creative Commons Attribution 4.0 International License.…”

Section: Schottky Contacts To Ga2o3mentioning

confidence: 99%

“…Xian et al also studied the effect of different SC orientations on maximum achievable forward current density before failure and temperature distributions in the vertical SBDs . As shown in Figure c, various size square and rectangular SCs with the long axis perpendicular to either the [100] or [010] crystallographic directions were fabricated.…”

Section: Schottky Contacts To Ga2o3mentioning

confidence: 99%

“…However, after annealing at 500 °C for 60 s, the SBH was 0.81 and the ideality factor improved to 1.12. However, the W Schottky contact had a lower SBH than 203,204 They found that forward-bias stress caused reverse breakdown degradation and thermally induced failure on both the SC and the epilayer due to the low thermal conductivity of Ga 2 O 3 . The simulation of temperature distributions at forward bias under different current conditions revealed that maximum temperature rise (270−350 °C) occurs at the MS contact center.…”

Section: Schottky Contacts To Ga 2 Omentioning

confidence: 99%

“…205 Xian et al also studied the effect of different SC orientations on maximum achievable forward current density before failure and temperature distributions in the vertical SBDs. 204 As shown in Figure 17c, various size square and rectangular SCs with the long axis perpendicular to either the [100] or [010] crystallographic directions were fabricated. It was found that the rectangular SCs fabricated on the (001) epilayer with their long side perpendicular to the [010] orientation could sustain the largest current and showed greater resistance to thermal degradation under forward bias conditions as compared to the rectangular SCs with the long side perpendicular to the [100] direction and square shape SCs.…”

Section: Schottky Contacts To Ga 2 Omentioning

confidence: 99%

See 4 more Smart Citations

A Comprehensive Review on Recent Developments in Ohmic and Schottky Contacts on Ga₂O₃ for Device Applications

Sheoran

Kumar

Singh

2022

ACS Appl. Electron. Mater.

View full text Add to dashboard Cite

Ultrawide bandgap β-gallium oxide (β-Ga2O3) is emerging as a viable candidate for next-generation high-power electronics, including Schottky barrier diodes (SBDs) and field-effect transistors (FETs). This is due to its excellent material properties such as ultrawide bandgap of 4.6–4.9 eV, high breakdown electric field of 8 MV/cm, very high Baliga’s figure of merit (BFOM) and mature technology for large bulk single crystals, and epitaxial techniques with controllable n-type doping. Ohmic and rectifying metal–semiconductor contacts on β-Ga2O3 have been developed over the past decade. This work comprehensively reviews the recent development of metal–semiconductor contacts on β-Ga2O3. We start with basic concepts of metal–semiconductor contacts, which is followed by summarizing the current literature on ohmic and Schottky contacts on β-Ga2O3. Finally, the status of high-power Schottky diode contact on β-Ga2O3 is presented.

show abstract

Section: Schottky Contacts To Ga2o3mentioning

confidence: 99%

Section: Schottky Contacts To Ga2o3mentioning

confidence: 99%

Section: Schottky Contacts To Ga2o3mentioning

confidence: 99%

Section: Schottky Contacts To Ga 2 Omentioning

confidence: 99%

Section: Schottky Contacts To Ga 2 Omentioning

confidence: 99%

See 3 more Smart Citations

A Comprehensive Review on Recent Developments in Ohmic and Schottky Contacts on Ga₂O₃ for Device Applications

Sheoran

Kumar

Singh

2022

ACS Appl. Electron. Mater.

View full text Add to dashboard Cite

show abstract

Distinct Contact Scaling Effects in MoS₂ Transistors Revealed with Asymmetrical Contact Measurements

et al. 2023

View full text Add to dashboard Cite

were developed to form the basis for understanding these contacts. [2][3][4][5][6] Since the invention of the transistor, [7] the development of Ohmic contacts has been a major research topic in advancing various transistor technologies. [8,9] During the decades of research and especially with the development of different measurement methods (e.g., the transmission line method), [10] it was expected that charge carriers crowd near the bottom edge of planar metal contacts, that is, only a fraction of the contact is employed for active carrier injection. This current-crowding phenomenon significantly affects how small the contacts can be scaled without limiting drain currents.To achieve higher device density in a certain chip area, it is key to reduce all device dimensions (device scaling). In this context, nowadays one of the significant frontiers for studying the metal-semiconductor contacts is their scaling behavior (i.e., how reducing device dimensions impacts device operation and performance), manifested mainly in two trends. First, the thickness of semiconductor channel materials has been reduced with the advent of atomically thin semiconductors [11][12][13][14] and the development of gate-all-around nanosheet transistors. [15] This trend can be considered channel thickness scaling. Second, the metal contact length (L c ), the length where metal 2D semiconducting materials have immense potential for future electronics due to their atomically thin nature, which enables better scalability. While the channel scalability of 2D materials has been extensively studied, the current understanding of contact scaling in 2D devices is inconsistent and oversimplified. Here physically scaled contacts and asymmetrical contact measurements (ACMs) are combined to investigate the contact scaling behavior in 2D field-effect transistors. The ACMs directly compare electron injection at different contact lengths while using the exact same MoS 2 channel, eliminating channel-to-channel variations. The results show that scaled source contacts can limit the drain current, whereas scaled drain contacts do not. Compared to devices with long contact lengths, devices with short contact lengths (scaled contacts) exhibit larger variations, 15% lower drain currents at high drain-source voltages, and a higher chance of early saturation and negative differential resistance. Quantum transport simulations reveal that the transfer length of Ni-MoS 2 contacts can be as short as 5 nm. Furthermore, it is clearly identified that the actual transfer length depends on the quality of the metal-2D interface. The ACMs demonstrated here will enable further understanding of contact scaling behavior at various interfaces.

show abstract

Effect of Ar‐Based Reactive Ion Etching on the Ohmic Contacts in Gallium Oxide Field Effect Transistor

Kachhawa,

Jain,

Chaturvedi

2023

Physica Status Solidi (a)

View full text Add to dashboard Cite

Herein, ultra‐wideband gap semiconductor β‐gallium oxide (β–Ga2O3) over sapphire ( orientation) is investigated for ohmic contact improvement with the help of argon (Ar)‐based reactive ion etching (RIE). Postannealing effects of these contacts over ( orientation) gallium oxide samples are also investigated. The surface defects and oxygen vacancies generated by Ar etching lead to the formation of as‐deposited ohmic contacts with the Ti/Au metal stack. A contact resistance of 10.52 Ω mm with a specific contact resistivity of 2.24 × 10−4 Ω cm2 is achieved with 10 min Ar RIE prior metallization. However, the contacts further degrade when samples are subjected to annealing. The electrical measurements and energy‐dispersive X‐ray spectroscopy elemental mappings at samples after annealing reveal that it is due to the formation of titanium oxide (TiOx) compound which acts as an insulator and concurrent with the out‐diffusion of Ga and in‐diffusion of gold. These results show the impact of anisotropy of gallium oxide over different annealing temperatures. These results and techniques may pave the way for better ohmic contacts for gallium oxide‐based high‐voltage and high‐power applications.

show abstract

Asymmetrical Contact Geometry to Reduce Forward-Bias Degradation in β-Ga₂O₃ Rectifiers

Cited by 12 publications

References 55 publications

A Comprehensive Review on Recent Developments in Ohmic and Schottky Contacts on Ga₂O₃ for Device Applications

A Comprehensive Review on Recent Developments in Ohmic and Schottky Contacts on Ga₂O₃ for Device Applications

Distinct Contact Scaling Effects in MoS₂ Transistors Revealed with Asymmetrical Contact Measurements

Effect of Ar‐Based Reactive Ion Etching on the Ohmic Contacts in Gallium Oxide Field Effect Transistor

Contact Info

Product

Resources

About

Asymmetrical Contact Geometry to Reduce Forward-Bias Degradation in β-Ga2O3 Rectifiers

Cited by 12 publications

References 55 publications

A Comprehensive Review on Recent Developments in Ohmic and Schottky Contacts on Ga2O3 for Device Applications

A Comprehensive Review on Recent Developments in Ohmic and Schottky Contacts on Ga2O3 for Device Applications

Distinct Contact Scaling Effects in MoS2 Transistors Revealed with Asymmetrical Contact Measurements

Effect of Ar‐Based Reactive Ion Etching on the Ohmic Contacts in Gallium Oxide Field Effect Transistor

Contact Info

Product

Resources

About

Asymmetrical Contact Geometry to Reduce Forward-Bias Degradation in β-Ga₂O₃ Rectifiers

A Comprehensive Review on Recent Developments in Ohmic and Schottky Contacts on Ga₂O₃ for Device Applications

A Comprehensive Review on Recent Developments in Ohmic and Schottky Contacts on Ga₂O₃ for Device Applications

Distinct Contact Scaling Effects in MoS₂ Transistors Revealed with Asymmetrical Contact Measurements