{
  "id": 6158850,
  "title": "New nitride semiconductor expands material options for more powerful electronics",
  "url": "https://urgent.news/2026/09/07/new-nitride-semiconductor-expands-material-options-for-more-powerful",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-07T19:00:06.000Z",
  "source": {
    "name": "Phys.org",
    "slug": "phys-org",
    "url": "https://phys.org/news/2026-09-nitride-semiconductor-material-options-powerful.html"
  },
  "original_language": "en",
  "account": "Polar wurtzite nitride semiconductors like aluminum nitride (AlN) and gallium nitride (GaN) play essential roles in modern high-power and high-frequency electronic devices due to their wide band gaps, high breakdown electric fields, and strong electric polarization. At the AlN/GaN interfaces, these properties enable the formation of a two-dimensional electron gas (2DEG) with high carrier density and mobility, which is crucial for the operation of GaN high-electron-mobility transistors (HEMTs). Wurtzite nitrides are key to various functions, from conventional piezoelectric actuation to ferroelectric switching.\n\nThe discovery of scandium aluminum nitride (ScAlN) was a significant milestone, inspiring further research into polar wurtzite alloys. Transition metal alloying, particularly with niobium (Nb), has attracted attention, as Nb is readily available and suitable for sputter deposition. However, incorporating Nb into AlN while maintaining a long-range wurtzite crystal structure, epitaxial quality, and uniform metal polarity has been challenging.\n\nIn a breakthrough study led by Dr. Atsushi Kobayashi from Tokyo University of Science (TUS), Japan, researchers from the University of Tokyo and Mie University successfully grew single-crystalline polar wurtzite NbAlN thin films on GaN substrates for the first time. This achievement demonstrates that NbAlN belongs to a new class of transition-metal-containing polar nitride semiconductors, preserving the wurtzite crystal structure and metal polarity of GaN. The NbAlN films maintained their coherence up to 25% Nb content, but surface roughening and degraded crystal quality occurred at higher Nb concentrations.\n\nAtomic-resolution scanning transmission electron microscopy revealed that Nb incorporation resulted in the same metal-polar stacking as the underlying GaN in the observed regions. Even with compositional variations, the wurtzite lattice remained continuous without grain boundaries or secondary phases. The researchers incorporated NbAlN barrier layers into AlGaN/AlN/GaN reference heterostructures, resulting in a threefold increase in sheet electron density and higher room-temperature electron mobility. These findings suggest that NbAlN can serve as a polarization-engineered layer, potentially enhancing the performance of GaN heterostructures in power and RF semiconductor devices.\n\nThe study opens up new possibilities for designing carrier density in GaN devices by incorporating transition-metal-containing polar nitride semiconductors like NbAlN. Future research will focus on measuring polarization constants, examining interface and impurity effects in greater detail, and fabricating transistors to evaluate the practical implications of these findings. Dr. Kobayashi concludes that this work establishes a new family of polar nitride semiconductors, expanding the options for designing high-performance GaN heterostructures.",
  "summary": "Polar wurtzite nitride semiconductors, such as aluminum nitride (AlN) and gallium nitride (GaN), are central to modern high-power and high-frequency electronic devices because of their wide band gaps, high breakdown electric fields, and strong spontaneous and piezoelectric polarization.",
  "key_points": [
    "Tokyo University of Science researchers grow single-crystalline NbAlN thin films on GaN substrates.",
    "NbAlN maintains wurtzite crystal structure and metal polarity up to 25% Nb content.",
    "NbAlN enhances electron mobility in GaN heterostructures by threefold."
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}