Fraunhofer Institute for High Frequency Physics and Radar Techniques FHR
Fraunhofer FHR's on-wafer measurement technology provides comprehensive characterization capabilities for integrated circuits, with a particular focus on radio-frequency (RF) and microwave applications. As an essential element of integrated circuit development and validation, it enables the experimental investigation of device characteristics over a broad frequency range. In addition to wafer-level measurements, individual diced chips can also be characterized. The infrastructure therefore supports the development, optimization, and qualification of modern RF integrated circuits, ranging from discrete components to highly integrated systems.
The measurement infrastructure is located at Ruhr University Bochum and is operated as part of a joint laboratory with the Chair of Integrated Systems. At the core of the facility is a Summit 12000M wafer probe station which, in combination with a variety of measurement instruments, enables detailed characterization of integrated circuits. This infrastructure supports reproducible on-wafer measurements and allows circuits to be thoroughly evaluated throughout the development process.
Vector Network Analysis
For vector network analysis, measurement capabilities with up to four ports are available over a frequency range from 900 Hz to 67 GHz. In addition, band-limited two-port measurement setups based on rectangular waveguides are available. These cover frequencies from the W-band (75-110 GHz) up to the WR2.2 waveguide band (325-500 GHz). This enables the characterization of integrated RF circuits such as amplifiers, as well as passive components including couplers and attenuators. Furthermore, the measurement setups can be used for the characterization of dielectric materials. The broadband network analysis capability allows precise determination of scattering parameters (S-parameters) and supports the development of circuits and components for RF, millimeter-wave, and terahertz applications.
Signal, Spectrum, and Noise Analysis
Additional characterization capabilities are provided by signal and spectrum analysis. Direct measurements can be performed up to 85 GHz. Using waveguide-based harmonic mixers, the measurement range can be extended to frequencies between 75 GHz and 325 GHz. Various power sensors further support spectral characterization within this frequency range. In addition, the noise performance of RF circuits can be investigated using several methods based on vector network analysis as well as signal and spectrum analysis over a frequency range from 10 MHz to 67 GHz. These capabilities enable detailed evaluation of amplifiers, oscillators, receiver front-ends, and other key components of modern RF and microwave systems.
Characterization Under Controlled Temperature Conditions
For measurements under controlled thermal conditions, the on-wafer measurement system can routinely be operated at temperatures ranging from approximately −10 °C to +125 °C. Under certain constraints, this range can be extended down to −40 °C. This capability allows integrated circuits to be characterized under varying temperature conditions and enables systematic investigations of changes in their electrical and RF performance. Temperature-dependent characterization provides valuable insights for applications in which electronic components must operate reliably under demanding environmental conditions.
Application Areas at Fraunhofer FHR
On-wafer characterization is a key element in the development and validation of integrated circuits. At Fraunhofer FHR, the measurement infrastructure is used primarily for circuits based on silicon-germanium (SiGe) technologies. Applications range from cryogenic low-noise amplifiers (LNAs) to components for terahertz systems. The infrastructure therefore complements Fraunhofer FHR's research and development activities in the field of highly integrated RF and microwave components and advanced high-frequency systems.