KEYWORDS: Temperature metrology, Cryogenics, Transistors, Data modeling, Advanced distributed simulations, Modeling, Field effect transistors, Semiconducting wafers, 3D modeling, Thermal modeling
The main objectives of this work concerns the on-wafer high frequency noise measurements of low noise transistors (GaAs and InP HEMTs) at cryogenic temperature. We propose a new approach to de-embed the measured noise figure or noise power by taking into account the temperature distribution of the whole bench. For measurements at 77K, the gradient of temperature between the DUT and the receiver or the noise source is greater than 200K and the temperature distribution along the probes and cables is non uniform. This temperature distribution has to be accurately known to de-embed the measured noise figure and especially for low noise device like lattice-matched or metamorphic HEMTs.
The temperature distribution along the probes and cables is obtained using a 3-D thermal modeling (ANSYS) and has been checked through thermal sensors measurements. The inputs of the thermal simulations are the material composition and associated thermal properties of the probes, connectors and cables. This temperature distribution associated to a RLCG transmission line are afterwards implemented in CAD tool (ADS). In order to check the validity of such model, we have measured the noise power of a 50 Ω resistance for different temperatures (77 K to 295 K). At 77 K, after a de-embedding procedure using the distributed temperature model, we obtain an equivalent noise temperature of the resistance of 77 K ± 10 K. This de-embedding method will be applied to extract the noise parameters of cooled down HEMTs.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.