Theoretical and experimental analysis of the source resistance components in In0.7Ga0.3As quantum-well high-electron-mobility transistors

• Published in: Journal of the Korean Physical Society Vol. 78; no. 6; pp. 516 - 522
• Main Authors: Lee, In-Geun, Ko, Dae-Hong, Yun, Seung-Won, Kim, Jun-Gyu, Jo, Hyeon-Bhin, Kim, Dae-Hyun, Tsutsumi, Takuya, Sugiyama, Hiroki, Matsuzaki, Hideaki
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Physical Society 01.03.2021; Springer Nature B.V; 한국물리학회
• Subjects: Computer networks; Contact resistance; High electron mobility transistors; Mathematical and Computational Physics; Model accuracy; Original Paper; Particle and Nuclear Physics; Physics; Physics and Astronomy; Quantum wells; Semiconductor devices; Substrates; Theoretical; Transistors; Transmission lines; 물리학; InGaAs; Source resistance; Transfer length; HEMT; Sheet resistance; Contact
• ISSN: 0374-4884; 1976-8524
• DOI: 10.1007/s40042-021-00096-0

Herein we describe theoretical and experimental analysis of the source resistance ( R s ) components in In 0.7 Ga 0.3 As/In 0.52 Al 0.48 As quantum-well (QW) high-electron-mobility transistors (HEMTs) on an InP substrate. First, we analytically modeled R s using a three-layer formula, separately modeling the regions of the ohmic contact, the gate-to-source access, and the side-recessed regions. The resistances of the ohmic contact and access regions were analyzed in a distributed-network manner with two different transfer lengths, whereas the resistance associated with the side-recess region near the gate edge was modeled by using a lumped element. To verify the accuracy of the proposed R s model, we fabricated two different types of transmission-line-method (TLM) test patterns as well as long-channel In 0.7 Ga 0.3 As/In 0.52 Al 0.48 As QW HEMTs, and compared their measured and modeled R s . The modeled R s was in excellent agreement with the measured R s from the recessed TLM patterns and the long-channel HEMTs. Since the widths of the ohmic contact to the heavily doped In 0.53 Ga 0.47 As capping layer and the gate-to-source access region were typically much greater than corresponding transfer lengths ( L T _ cap and L T _ barrier ), those distributed networks could be simplified to a lumped-element based one-layer model, revealing that the tunneling resistance ( R barrier ) through the In 0.52 Al 0.48 As barrier should be carefully considered to minimize the R s of In x Ga 1− x As QW HEMTs together with S/D contact resistances and L GS .