Meeting the increasing demand for higher energy-conversion efficiency requires a much faster power switch than is possible with silicon. The material properties of Gallium Nitride (GaN) enable such a switch – the power GaN high-electron mobility transistor (HEMT) is a field-effect transistor (FET) that has lower ON resistance and can switch faster than a silicon power transistor of the same size. And, since the GaN HEMT can be grown on silicon substrates, it is compatible with silicon manufacturing, thus avoiding a cost penalty.
Despite these well-known advantages, the adoption rate for GaN power devices consistently lags market forecasts.
Noting that, “increasing worldwide energy efficiency by just 1% could shutter about 55 coal power plants,” Texas Instruments researcher Sandeep Bahl is urging an industry-wide collaboration to develop new reliability-test standards for GaN power transistors. In his blog, “Let’s GaN together reliably,” Bahl notes that though GaN passes stress-testing procedures developed for silicon, customers are justifiably wary: What does passing a 20-year old test mean for a new material in terms of device lifetime, failure rates and application relevance?
Bahl’s call for collaboration addresses a concern previously expressed by DOE’s Office of Electricity, “The power electronics industry must be assured of the reliability and performance of high power GaN‐on‐Si PE devices in real‐world applications. Lifetime failure testing and demonstrations are needed before widespread adoption can take place.”
“Standards are regarded as credible when an industry works together to develop them,” says Bahl, “the benefit of predictive reliability standards is a significant acceleration in market adoption.”