Improved GaN Substrates Prepared with Ammonothermal Growth

Tech ID: 23650 / UC Case 2006-666-0

Brief Description

A method for growing m-plane GaN using an ammonothermal growth technique.



The usefulness of gallium nitride (GaN) and its alloys has been well established for its use in the fabrication of optoelectronic and high-powered electronic devices. Most commercially available GaN-based devices are grown on conventional c-plane surfaces. The use of c-plane surfaces has disadvantages, which limit the performance of resulting devices. Recent studies have pointed out several benefits and advantages of growing m-plane devices. Despite these benefits, current technology is limited due to poor smoothness of m-plane surfaces.



Researchers at the University of California, Santa Barbara have developed a method for growing m-plane GaN using an ammonothermal growth technique. Using this method, m-plane growth results in smoother surfaces than c-plane growth. M-plane growth has associated benefits such as p-type doping and inverted polarization charge. High p-type conductivity improves device efficiency, while transistors grown on m-plane GaN overcome high gate leakage problems of traditional GaN transistors. M-plane optical devices also experience higher emission efficiency due to the absence of a polarization field, and their optically active layer usually has higher Indium incorporation, allowing for longer wavelength emission. This novel method also reduces processing steps because flip-chip bonding and de-bonding steps are no longer needed to expose the m-plane of the growth.



  • Smoother substrate surface
  • Improved device efficiency


  • LEDs and Laser Diodes
  • High Electron Mobility Transistors (HEMTs)
  • Power switching devices

Patent Status

Country Type Number Dated Case
United States Of America Issued Patent 8,263,424 09/11/2012 2006-666
United States Of America Issued Patent 7,755,172 07/13/2010 2006-666


Learn About UC TechAlerts - Save Searches and receive new technology matches


Other Information


indssl, indammono, ammonothermal, cenIEE, indbulk, indfeat

Categorized As

Additional Technologies by these Inventors