Wide-band-gap III-nitride semiconductors
Han, Jung Yale University, New Haven, Connecticut.
Nurmikko, Arto V. Brown University, Providence, Rhode Island.
- Optoelectronic applications
- High-power, high-temperature, and high-frequency electronics
- Epitaxial growth
- Device development
- White light strategy
- Links to Primary Literature
- Additional Readings
The band gap, or more precisely energy band gap, denotes the difference in energy between the highest valence electron energy states (valence band maximum) and the lowest conduction energy states (conduction band minimum). In optoelectronic devices, the band gap dictates the wavelength of light that a semiconductor absorbs and emits. The size of band gap also determines the ultimate robustness of electronic devices under high ambient temperature or excessive power loads. Semiconductors, including II–VI compounds, such as ZnSe, ZnS, and ZnO, have at times shared the label of wide-band-gap semiconductors by providing important proof-of-concept demonstrations of blue-green lasers and light-emitting diodes (LEDs) in the early 1990s. In a relatively short time, however, the nitride compounds with three of the column IIIA elements (AlN, GaN, and InN) have emerged as exceptionally versatile semiconductors, with functionalities unattainable from traditional Si and GaAs technologies. Compared to GaAs with an energy gap corresponding to infrared emission (890 nanometers), the AlGaInN family covers the entire visible spectrum from infrared (InN) to blue (InGaN), and extending into deep ultraviolet (AlGaN), creating opportunities in display, illumination, high-density optical storage, and biological and medical photonics (Fig 1). Performance of traditional Si devices is known to deteriorate at device temperatures above 100°C (212°F) or when the applied voltage exceeds certain critical electrical fields. Transistors and diodes made from wide-band-gap GaN are expected to create opportunities beyond low-power digital electronics, including applications in automobiles, aircraft, utility distribution, and wireless communications.
The content above is only an excerpt.
for your institution. Subscribe
To learn more about subscribing to AccessScience, or to request a no-risk trial of this award-winning scientific reference for your institution, fill in your information and a member of our Sales Team will contact you as soon as possible.
to your librarian. Recommend
Let your librarian know about the award-winning gateway to the most trustworthy and accurate scientific information.
AccessScience provides the most accurate and trustworthy scientific information available.
Recognized as an award-winning gateway to scientific knowledge, AccessScience is an amazing online resource that contains high-quality reference material written specifically for students. Contributors include more than 9000 highly qualified scientists and 43 Nobel Prize winners.
MORE THAN 8700 articles covering all major scientific disciplines and encompassing the McGraw-Hill Encyclopedia of Science & Technology and McGraw-Hill Yearbook of Science & Technology
115,000-PLUS definitions from the McGraw-Hill Dictionary of Scientific and Technical Terms
3000 biographies of notable scientific figures
MORE THAN 19,000 downloadable images and animations illustrating key topics
ENGAGING VIDEOS highlighting the life and work of award-winning scientists
SUGGESTIONS FOR FURTHER STUDY and additional readings to guide students to deeper understanding and research
LINKS TO CITABLE LITERATURE help students expand their knowledge using primary sources of information