Electrical Properties of GaN Cap Layer for AlGaN/GaN HEMT

Abstract:

Metal organic chemical vapor deposition (MOCVD) was used to grow AlGaN/GaN HEMT on a sapphire substrate with a 3.0 nm GaN cap and a sample without a GaN cap. High resolution X-ray diffraction (HRXRD) was utilized to investigate the structural characteristics of the materials. The relationship between the electrical properties and two-dimensional electron gas (2DEG) I-V and Hall Effect measurement. The I-V measurement was used to investigate the resistance properties of AlGaN/GaN heterostructures. Hall Effect measurement was used to quantify electron mobility and sheet carrier concentration in both samples. The sample with a 3.0 nm GaN cap exhibited excellent electrical properties with 436.8 Ω/sq sheet resistivity and possessed a high value of sheet carrier concentration 3.46E+14 per cm².

• Periodical: Key Engineering Materials (Volume 947)
• Pages: 3-8
• DOI: https://doi.org/10.4028/p-9qdk55
• Online since: May 2023
• Authors: Mohamad Hasnan Abdull Hamid, Rahil Izzati Mohd Asri, Mohammad Nuzaihan, Masafumi Inaba, Zainuriah Hassan, Hiroshi Kawarada, Shaili Falina, Mohd Syamsul*
• Keywords: AlGaN/GaN, GaN Cap, HEMT

References

[1] B. Veigas, E. Fortunato, and P. V. Baptista, "Field effect sensors for nucleic acid detection: Recent advances and future perspectives," Sensors (Switzerland), vol. 15, no. 5. 2015.

DOI: 10.3390/s150510380

[2] S.-K. Cho and W.-J. Cho, "High-Sensitivity pH Sensor Based on Coplanar Gate AlGaN/GaN Metal-Oxide-Semiconductor High Electron Mobility Transistor," Chemosensors, vol. 9, no. 3, p.42, 2021.

DOI: 10.3390/chemosensors9030042

[3] P. Waltereit et al., "Impact of GaN cap thickness on optical, electrical, and device properties in AlGaN/GaN high electron mobility transistor structures," J. Appl. Phys., vol. 106, no. 2, 2009.

DOI: 10.1063/1.3184348

[4] Y. Xia et al., "Effects of the cap layer on the properties of AlN barrier HEMT grown on 6-inch Si(111) substrate," Mater. Res. Express, vol. 7, no. 6, 2020.

DOI: 10.1088/2053-1591/ab96f5

[5] N. Chugh, M. Kumar, M. Bhattacharya, and R. S. Gupta, "Sheet carrier concentration and current–voltage analysis of Al0.15Ga0.85N/GaN/Al0.15Ga0.85N double heterostructure hemt incorporating the effect of traps," Microsyst. Technol., 2019.

DOI: 10.1007/s00542-019-04322-5

[6] H. Kang et al., "Effects of a GaN cap layer on the reliability of AlGaN/GaN Schottky diodes," Phys. Status Solidi Appl. Mater. Sci., vol. 212, no. 5, p.1158–1161, 2015.

DOI: 10.1002/pssa.201431719

[7] B. Duan, L. Yang, Y. Wang, and Y. Yang, "Experimental Results for AlGaN/GaN HEMTs Improving Breakdown Voltage and Output Current by Electric Field Modulation," IEEE Trans. Electron Devices, vol. 68, no. 5, p.2240–2245, 2021.

DOI: 10.1109/TED.2021.3067865

[8] Y. J. Choi, J. Lee, S. J. An, and K. Im, "Low-Frequency Noise Behavior of AlGaN / GaN," 2020.

[9] R. Loganathan, M. Jayasakthi, K. Prabakaran, R. Ramesh, P. Arivazhagan, and K. Baskar, "Studies on dislocation and surface morphology of AlxGa 1-xN/GaN heterostructures grown by MOCVD," J. Alloys Compd., vol. 616, p.363–371, 2014.

DOI: 10.1016/j.jallcom.2014.07.170

[10] P. Cui et al., "Influence of different GaN cap layer thicknesses on electron mobility in AlN/GaN heterostructure field-effect transistors," Superlattices Microstruct., vol. 100, 2016.

DOI: 10.1016/j.spmi.2016.09.039

[11] C.-H. Li, Y.-C. Jiang, H.-C. Tsai, Y.-N. Zhong, and Y. Hsin, "Device Characteristics of AlGaN/GaN HEMTs with p-GaN Cap Layer," ECS J. Solid State Sci. Technol., vol. 6, no. 11, pp. S3125–S3128, 2017.

DOI: 10.1149/2.0281711jss