Highly efficient InGaN/GaN blue LEDs on large diameter Si (111) substrates comparable to those on sapphire
2011
Highly efficient InGaN/GaN LEDs grown on 4- and 8-inch silicon substrates comparable to those on sapphire
substrates have been successfully demonstrated. High crystalline quality of n-GaN templates on Si were obtained by
optimizing combination of stress compensation layers and dislocation reduction layers. The full-width at half-maximum
(FWHM) values of GaN (0002) and (10-12) ω-rocking curves of n-GaN templates on 4-inch Si substrates were 205 and
290 arcsec and those on 8-inch Si substrate were 220 and 320 arcsec, respectively. The dislocation densities were
measured about 2~3×10 8 /cm 2 by atomic force microscopy (AFM) after in-situ SiH 4 and NH 3 treatment. Under the unencapsulated
measurement condition of vertical InGaN/GaN LED grown on 4-inch Si substrate, the overall output power
of the 1.4×1.4 mm 2 chips representing a median performance exceeded 504 mW with the forward voltage of 3.2 V at the
driving current of 350 mA. These are the best values among the reported values of blue LEDs grown on Si substrates.
The measured internal quantum efficiency was 90 % at injection current of 350 mA. The efficiency droops of vertical
LED chips on Si between the maximum efficiency and the efficiency measured at 1A (56.69 A/cm 2 ) input current was
5%.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
0
References
9
Citations
NaN
KQI