RF performance characterisation test can be on-wafer for repeatability
Combining an R&S ZNA vector network analyser and device characterisation test from engineering probe system specialist, FormFactor, Rohde & Schwarz offers full RF performance characterisation of the device under test (DUT) on-wafer, allowing semiconductor manufacturers to perform reliable and repeatable on-wafer device characterisation in the development phase, during product qualification and in production.
5G RF front-end designers aim to ensure proper RF capabilities for frequency coverage and output power while optimising energy efficiency. It is important to investigate the RF performance, to get feedback on the design as early as possible and assess the performance and capabilities already on the wafer level, explained Rohde & Schwarz. Characterising a DUT in an on-wafer environment requires a measurement system which includes a vector network analyser (VNA), a probe station, RF probes, cables or adapters, a dedicated calibration method as well as calibration substrates for the particular DUT or application.
The R&S ZNA VNA characterises all RF qualification parameters at coaxial and waveguide levels, as well as frequency extenders for application ranges above 67GHz. FormFactor’s manual, semi-automated and fully automated probe systems including thermal control, high-frequency probes, probe positioners, and calibration tools, addresses the wafer contact.
The calibration of the complete test system, including the R&S ZNA, is fully supported in the FormFactor WinCal XE calibration software.
In the test setup, the calibrated set up allows the user access to all test capabilities of the R&S ZNA. Generic S-parameter tests allow characterisation for filters and active devices, but distortion, gain and intermodulation tests can also be performed to qualify power amplifiers. Frequency translating measurements for mixers with phase characterisation across the bandwidth of the device are also supported. The fully calibrated set ups also allow all results to be directly taken from the VNA without post processing as the calibration data are applied directly to the VNA. Frequency extenders from Rohde & Schwarz open up sub-THz frequencies such as D-band, currently in the focus of 6G research.
The extenders will be integrated to the probe station to ensure shortest cabling and enable optimal dynamic range while avoiding losses due to cabling to the probe tip, confirmed Rohde & Schwarz.