The goal of this research is to mature high-temperature electronics packaging systems to a technology readiness level (TRL) of 5. More specifically, we will design, assemble and evaluate packaged electronics components and materials (die attach, wire bond metal, package interconnect, substrates, and anti-fouling nano-coatings) in ground-based relevant environments using simulation pressure chambers at NASA (Glenn Extreme Environment Rig) and University of Arkansas (Parr Instruments Model #4652). Since current packaging technology fails much below 500°C, typical space-grade electronics packaging approaches require extensive cooling systems and radiation shielding to prevent degradation during operation, which significantly increases cost and payload. As a result, new electronic platforms that utilize high-temperature, weather-resistant (e.g., sulfur haze/rain) packaging architectures are proposed to support NASA missions to Venus, Mercury or gas giants. Extreme electronics packaging technology developed at the University of Arkansas has demonstrated SiC integrated circuits and power devices on ceramic substrates operating at 400°C in air atmosphere. In addition, Stanford University has performed preliminary Venus weathering studies and sulfuric acid tests on potential packaging materials (including commercial superhydrophobic nano-coatings) and has a variety of high-temperature (600°C demonstrated) wide bandgap (GaN and SiC) electronic test vehicles/devices. In the proposed program, two types of wide bandgap electronic test vehicles/devices will be packaged and exposed to chemically corrosive, high temperature working environments and the behavior (mechanical, electrical and thermochemical) will be evaluated in a systematic fashion. The scope of the proposed research is to (1) leverage existing designs of wide bandgap test devices (e.g., SiC and GaN diodes) with high-temperature metallization as test vehicles for high-temperature packaging schemes; (2) develop a high-temperature packaging architecture for SiC and GaN devices using 500°C capable die attach and metal interconnect technology on ceramic substrates; (3) integrate nanotextured anti-fouling films onto housing surfaces to enable weather-resistant packaging schemes and probe structures; (4) perform long-term thermal and chemical exposure tests on packaging materials and actual packaged devices using high-temperature furnaces (Stanford) and relevant simulation pressure vessels (NASA and University of Arkansas); and (5) analyze experimental data and make specific recommendations to NASA for selection of packaging materials and design schemes to realize HOTTech-relevant systems. When successful, these tasks aid in the realization and maturity of highly functional and robust packaging for electronic systems and subsystems that may be used for the scientific exploration of Venus, Mercury or gas giants, as well as oil wellbores and enhanced geothermal systems. Ultimately, the robust packaging technology developed in this program supports NASA’s technical research areas such as TA12 (materials that can survive the space environment and lightweight structures with reduced packaging) and TA10 (sensors, electronic and devices, miniature instruments) as described in the Space Technology Roadmap (STR). In addition, the potential for commercialization in numerous ground-based applications (e.g., energy, combustion, industrial) will be explored.