Chip with micro-hotplate for self-healing and sustainable electronics

electrical and electronics
Chip with micro-hotplate for self-healing and sustainable electronics (TOP2-278)
An on-chip immune system against hot-carrier stress, bias temperature instability, and total ionizing dose degradation
Exposure to various types of radiation or even natural aging mechanisms causes undesired defects in materials used to construct modern integrated circuits that could result in system malfunction or even catastrophic mission failure. NASA Ames has developed a patent-pending technology, an on-chip annealing system based on a monolithically integrated micro-heater. This technology of self-healing electronics, with a micro-hotplate embedded on the unused back side of the chip, provides a new way of improving the recovery of a Metal-Oxide-Semiconductor (MOS) transistor that has been exposed to a radiation pulse. This novel approach not only provides high radiation immunity but also enhances the robustness of space electronics, particularity for small satellites where expensive radiation hardening is not affordable. This technology is also valuable for critical applications in the terrestrial environment.

The Technology
Heat treatment, also known as annealing, is a common step in the semiconductor fabrication process. A build-up of radiation-induced localized charge within the semiconductor and insulator alters local field distribution, threshold voltage and leakage current. NASA's patent-pending technology implements an annealing process on a system level directly on a chip for annealing defects and improving device performance with heating done in the laboratory. The annealing may be performed inside an oven, or upon a hotplate. A system on microheater provides defect annealing capability for recovering bulk trapped charges and interface states. The healing starts simply by heating the chip in a process that can be compared to that of humans immune system - something capable of detecting and quickly responding to any number of possible assaults in order to keep the larger system working optimally. A microheater is monolithically integrated on the backside of a generic Complementary Metal Oxide Semiconductor (CMOS) chip for an on-chip annealing system (left Figure 1(b)). Compared to a stacked microheater, the monolithic integration reduces the die profile, which accordingly enhances the heating power efficiency and heating/cooling rates, which was verified experimentally and numerically. The self-healing microheater is controlled by a temperature feedback circuit to maintain the desired temperature. All circuits under the treatment are unbiased in order to avoid any side effects on normal devices. A control circuit block is programmed to monitor a device parameter shift such as the threshold voltage on the same chip in order to determine the need for treatment. A control circuit triggers the micro hotplate and senses the temperature to adjust the target temperature and duration. The microheater and the system-on-chip are fabricated separately and stacked into a single package, which can be implemented on any arbitrary commercial-off-the-shelf device as a generic approach.
Micro-chip Left- Figure 1: (a) heater die stacked version and (b) monolithically integrated heater version
Right- Figure 2: (a) Schematic illustration of self-healing architecture and (b) schematic and images of the fabricated chip
  • High radiation immunity to any COTS (commercial off the shelf) transistor and chip
  • Saves payload weight and launching costs
  • Enhanced heating power efficiency
  • Reduced fabrication complexity
  • Lower die profile
  • High endurance and reliability
  • Potentially increases the on-chip curing temperature due to its direct microheater integration
  • Built-in self-test circuit may be embedded to monitor vital signs of the circuit
  • Trigger the self-healing process, examine the recovery of degradation, and decide when to stop the remedy process
  • The temperature can also be monitored by built-in sensors

  • Electronic devices both space electronics and ultra-small terrestrial electronics
  • Micro-hotplate-based devices
  • Microelectronic industry
  • Flash memory applications
  • Space industry
  • Semiconductor industry
Technology Details

electrical and electronics
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