These self-repairing semiconductor designs can be integrated into computer processors for radio communication in high temperature or high radiation environments. Worldwide sales of semiconductors in 2014 reached $335.8 billion, up 9.9 percent from 2013. Low-power satellites in outer space, cell phones and towers, or rugged military laptops use the toughest semiconductors available. They relay important information, such as GPS coordinates or digital messages. Because of hostile environmental conditions, quick temperature changes, and normal wear and tear, this expensive equipment needs regular replacement. Semiconductor manufacturers often use Gallium Nitride-based HEMT (High-electron-mobility transistor) semiconductors for radio frequency communications and direct current power. HEMTs are fast and resistant to noise, but HEMTs are not immune to all threats. Stresses such as moisture, localized heat, and voltage spikes might decrease processor performance, increase power consumption, and eventually lead to circuit failure. Thermal annealing -- applying a uniform heat source -- can undo some of that damage, but available methods are not feasible. Researchers at the University of Florida have developed an on-chip heater with a preset drain or gate current level. Now, whenever semiconductor chips conditions reach that preset level, an internal heater could turn on automatically and begin annealing the chips. After annealing, these chips could return to near-original electrical operating condition. No outside maintenance by the device owner would be needed.
High-performance, longer-lasting, self-repairing semiconductors for RF communication, AC to DC power conversion, and DC power amplification
The patent-pending semiconductor designs include an on-chip or on-substrate heater with a preset drain or gate current level. When the semiconductor conditions reach the preset level, the heater will automatically turn on and thermally anneal the chips. Research shows annealing will reverse or partially reverse effects such as forward and reverse bias current increase, the appearance of traps, sub-threshold swing increase, sub-threshold leakage increase, reverse bias gate leakage current increase, saturation drain current reduction, drain current on-off ratio reduction, gate current reduction, lower electromagnetic Schottky barriers, higher diode ideality factors, weaker small signal RF, and degradation at a metal-Aluminum Gallium Nitride interface. Overall, since a chip can regain lost performance even after multiple heat treatments, its life expectancy will increase.