3D X-Ray CT for Research on Power Electronics Components, Materials, and Packaging for Reliable Naval Power Electronic Power Distribution Systems
Abstract
The Power Electronic Power Distribution System (PEPDS) is a new power, energy, and control distribution concept proposed by the Office of Naval Research (ONR) to improve the adaptability, reliability, and resiliency of Navy ships. PEPDS is enabled by ONR-developed technologies, including high-power-density, high-efficiency power electronics converters and silicon carbide (SiC) power semiconductor devices. It represents a new paradigm of power distribution systems, utilizing modular Power Electronics Building Block (PEBB)-based converters. The Center for Power Electronics (CPES) at Virginia Tech is researching materials, components, packaging, and converters to realize reliable, high-density PEBBs and PEBB-based converters that will enable this PEPDS vision.Through this DURIP, CPESproposes to acquire 3D X-ray computed tomography (XCT) equipment to address key science and technology gaps that are limiting the reliability, performance, and power density of PEBBs. Such equipment will help us achieve this goal by accelerating our research and development efforts on innovative power semiconductor devices, bonding and insulation materials, 3D packaging structures, and medium-voltage converters. CPES is currently developing novel gallium nitride (GaN) power semiconductor devices to realize high-power-density PEBBs. In the current processing development, structural and failure analysis is routinely used. The current tools used for thisanalysis are expensive, time-consuming, and require the destruction of the devices to expose inner structures. The XCT can allow for non-destructive, fast, sub-micron imaging of intact samples, significantly reducing development cost and time. Further, the XCT system can allow for non-destructive failure analysis of power devices, which would be hugely beneficial to the processing developmentof power semiconductor devices, as well as their reliability and robustness studies.CPES has developed bonding and insulation nanomaterials and 3D module assembly technologies to enable the full potential of SiC and GaN power devices. An XCT imaging system that can non-destructively characterize structural defects or imperfections would significantly enhance these research efforts. Structuraldefects, such as microscopic voids or cracks, can form in bond lines, at boundaries between dissimilar materials, inside an encapsulant, or along the triple points on an insulated metal substrate. The defects can form during fabrication or in operation and are detrimental to performance and reliability. Having the ability to image these defects would help us understand the physical mechanismsfor their formation. The acquired knowledge can then be used to develop optimal processing conditions for higher fabrication yield and to guide the material selection and package design for higher reliability.CPES is developing high-power-density PEBBs utilizing 10 kV SiC power modules. The current prototype boasts a power density of over 10 MW/m3 and an efficiency of 99 %. However, due to the high voltages, electrical insulation remains a major challenge. XCT would enable a better understanding and mitigation of the voltage insulation issues. In particular, the XCT is essential to the inspection of the 10 kV SiC power modules, which experienced significant insulation degradation. XCT will enable detailed failure analysis and degradation monitoring to identify the root cause and physical mechanisms, which will be used to improve the module reliability. An XCT imaging system at Virginia Tech would enable us to rapidly address Navy needs for high-reliability, high-power-density, and high-performance PEBB-based converters.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 12, 2023
- Source ID
- N000142312207
Entities
People
- Christina DiMarino
Organizations
- Office of Naval Research
- United States Navy
- Virginia Tech