Discrete transistors withstand realistic radiation doses and rates

July 22, 2014 // By Graham Prophet
Bipolar transistors manufactured by STMicroelectronics are claimed to offer best-in-class rad-hard performance, and now carry a qualification for use in US projects. These JANSR+ (Joint Army Navy Space) 100krad low-dose-rate transistors offer improved performance for space and other radiative environments.

Adding to its available JANS / JANSR products, ST has introduced this range of DLA (Defense Logistics Agency)-qualified JANSR bipolar transistors with additional up-screening. Best-in-class radiation hardness makes ST's new transistors ideal for aerospace and Hi-Rel systems, including satellites, as well as nuclear physics and medical applications.

ST’s new rad-hard bi-polar transistors are available with maximum collector-emitter voltages up to 160V, maximum collector currents up to 5A, and forward current gains (hFE) up to 450.

ST has supported European aerospace applications since 1977, having been qualified by the European Space Agency since the Agency’s inception. Today, ST is bringing into the JANS system the innovation released last year within the ESCC (European Space Components Coordination) program. Called JANSR+, the innovation consists of a series of 100 krad JANSR high-dose-rate bipolar transistors with an additional 100 krad low-dose-rate (100 mrad/sec) test performed on each wafer. Furthermore, ST has announced it will complete its JANSR+ offer with data from very-low-dose-rate (10 mrad/sec) tests, demonstrating the outstanding robustness to radiation effect of its technology.

As a result, ST’s JANSR+ series gives access to products with superior performance in radiative environments, with complete test data to support the claim. These products can be used without any up-screen cost and lead time. All parts are housed in advanced hermetic UB packages.

STMicroelectronics; www.st.com/radhard-bipoltransistors-pr

ST adds the following notes;

(1) The effect of radiation on semiconductor devices depends on many factors. For bipolar transistors, the Total Dose (the higher the total dose, the higher the impact) and the dose rate (at a given Total Dose, the lower the dose rate the higher the impact) are the key factors. Low-dose-rate behaviour is critical for satellites, because dose rate in space is very low (in the range of 10 mrad/sec). However, the standard JANSR qualifications only deal with high dose rate, which is neither the worst case nor the condition the components typically have to endure in space.