HP TECHBRIEF7 free download

File name TECHBRIEF7.pdf

High-Frequency, Over-Temperature Measurements Recent advances in thermal probing stability of your system should be equipment have dramatically greater than -60 dB or 0.1%. You reduced the cost of obtaining tem- need to perform a new calibration perature-dependent S-parameter whenever the stability reaches data, while increasing throughput -40 dB or 1%. capabilities. These advances make These factors affect calibration thermal device modeling and stability: process characterization both practi- l Instrument variations over time. cal and affordable. The extreme l Probe placement errors resulting temperature range of interest from the wafer chucks thermal (-65o C to +2OO" C), however, expansion. increases the complexity of the cali- l Changes in the calibration stan- bration and measurement consider- dards with temperature. ations. l Electrical drift, due to probe and cable temperature variations. General Extraction Method To ensure measurement integrity, The most common extraction check calibration stability frequently. methods for temperature and bias- As the chuck changes tempera- dependent device modeling utilize Figure 1. Cascade's MicroChamber found on ture, it expands and contracts. The o cold-FET, pinched-FET, and hot- both manual and semi-automatic probing sys- total chuck expansion (from -65 C FET S-parameter m