NiCr resistors for terahertz applications in an InP DHBT process

In this article we report on the development of nickel-chrome (NiCr) thin film resistors (TFRs) for application in an Indium Phosphide (InP) Hetero-Bipolar Transistor process. We developed a stable process with low specific contact resistance, in which the sputtered NiCr is structured by lift-off. We measured a specific contact resistance to NiCr of 8 ×10−10 Ω ⋅ cm2. Furthermore we show the difficulties of structuring NiCr with an acid and connecting the NiCr from the top. Stress tests exhibited a high thermal resistance and high operation temperature of the NiCr on top of our BCB stack. Implemented NiCr resistors exhibit excellent agreement between simulation and measurement for high frequency applications. The utilization of the TFRs in microwave circuits showing excellent usability for microwave and terahertz applications. [Display omitted] •NiCr resistors developed for Terahertz applications in an InP transferred-substrate process•Lowest contract resistance (8 Ohm cm2 × 10–10) for NiCr resistors have been achieved with bottom connection•Top connected NiCr resistors showed high contact resistance (26.1 Ohm cm2 × 10–8) when opened by dry etching•Simulated and measured high frequency parameters are matching