We propose a new method to evaluate the polarization charge density induced at hetero-interfaces using capacitance-voltage characteristics of p-n heterojunctions and have applied this method to p-GaN/n-AlGaN heterojunction diodes. This method uses p-n heterojunction structures instead of undoped ones, so the obtained result is less influenced by background impurities or deep levels. Furthermore, it is possible to evaluate the negative polarization charge densities for GaN on top of AlGaN heterostructures. The experimental results indicate that the negative polarization charges with their densities more than 5 × 1012 cm-2 are induced at the GaN/AlGaN hetero-interfaces for the Al mole fractions above 11%.
|Number of pages||4|
|Journal||Physica Status Solidi C: Conferences|
|Publication status||Published - 2002 Dec 1|
|Event||2nd International Workshop on Nitride Semiconductors, IWN 2002 - Aachen, Germany|
Duration: 2002 Jul 22 → 2002 Jul 25
ASJC Scopus subject areas
- Condensed Matter Physics