NiZnAl-based p-type ohmic contacts on AlGaAs/InGaAs heterostructures

• Published in: IEEE transactions on electron devices Vol. 40; no. 6; pp. 1185 - 1187
• Main Authors: Abrokwah, J.K., Huang, J.H., Baker, J., Polito, T., Ooms, W.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.06.1993; Institute of Electrical and Electronics Engineers
• Subjects: Aluminum; Annealing; Applied sciences; Conductivity; Contact resistance; Electronics; Exact sciences and technology; HEMTs; Indium gallium arsenide; Interfaces; Metallization; MODFETs; Ohmic contacts; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Zinc; Field effect transistor; Gallium Indium Arsenides Mixed; Isolated gate field effect transistor; Ohmic contact; Aluminium Gallium Arsenides Mixed; Metallizing; Contact resistance; Chemical composition; Heterojunction
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/16.214753

p-type ohmic contacts based on Ni/Zn/Al/TiWN metallization were evaluated for application to self-aligned p-channel heterostructure FETs. Low-resistance, stable ohmic contacts were achieved on Al/sub x/Ga/sub 1-x/As/InGaAs heterostructures with aluminum composition (x) as high as 0.75. Following short-term annealing of 30 s in the temperature range of 500 degrees C to 600 degrees C, contact resistances less than 0.6 Omega -mm and specific resistivities under 5*10/sup -6/ Omega -cm/sup 2/ were achieved. Further anneal at 500 degrees C for 10 min resulted in a minimum contact resistance of 0.06 Omega -mm and a specific resistivity of 3.2*10/sup -8/ Omega -cm/sup 2/. Contact morphology was mirror-smooth and specular and the contacts were found to be stable at 500 degrees C for anneal times as long as 40 min, with contact resistance remaining below 1 Omega -mm.< >