Nearly lattice-matched n, i, and p layers for InGaN p-i-n photodiodes in the 365-500 nm spectral range

We report on nearly lattice-matched grown InGaN based p-i-n photodiodes detecting in the 365-500 nm range with tunable peak responsivity tailored by the i-layer properties. The growth of lattice matched i- and n-InGaN layer leads to improvement in the device performance. This approach produced photodiodes with zero-bias responsivities up to 0.037 A/W at 426 nm, corresponding to 15.5% internal quantum efficiency. The peak responsivity wavelength ranged between 416 and 466 nm, the longest reported for III-N photodiodes. The effects of InN content and i-layer thickness on photodiode properties and performance are discussed. (C) 2008 American Institute of Physics.