The recursive tiling of offspring dodecagons packed with random ensembles of squares and triangles in dilated parent cells forms the lattice. Additionally, the PQC rod dimension and pattern pitch were approximately 515 and 750 nm in this study according to  and roughly simulate calculation. EPZ-6438 mouse Besides, dry Selleck GSK2879552 etching depth of PQC structure was approximately 95 nm which was optimized through various depth etching, (the data is not shown here) since this etching depth could attain the best performance of light extraction efficiency
of our LED structure from our etching test experiments. Figure 3c,d shows the p-GaN surface and the n-side roughing regions of cross section SEM images with PQC PERK modulator inhibitor pattern, respectively. Further, the dry etching depth of the LED with PQC on n-side roughing was approximately 1.02 μm. Results and discussion Figure 4a shows the typical current–voltage (I-V) characteristics. It is found that the measured forward voltages under injection current
of 20 mA at room temperature for conventional LED, LED with PQC on p-GaN surface, LED with PQC on n-side roughing, and LED with PQC structure on p-GaN surface and n-side roughing were 3.11, 3.09, 3.14, and 3.15 V, respectively. In addition, the dynamic resistance of conventional LED, LED with PQC on p-GaN surface, LED with PQC on n-side roughing, and LED with PQC structure on p-GaN surface and n-side roughing are about 15.9, 16.7, 16.8, and 16.8 Ω, respectively. Therefore, in terms of dynamic resistance, there is no influence on this type of devices by incorporating PQC structure. The measured forward voltages at an injection current GPX6 of 20 mA at room temperature obtain similar I-V curves for all types of LEDs on PQC etching
depth in p-layer which was 95 nm. The coverage of ITO layer on p-GaN surface was uniform and no void defects on p-type contact, as the result in an ohmic contact in the contact area of the PQC structure on p-GaN surface, and the I-V curves of LEDs were almost similar while the etching depth of p-GaN surface was less than 95nm; however, the etching depth of p-layer was over 110 nm which indicated that there is heating and charging damages between ITO and p-GaN layer. Figure 4 Typical current–voltage ( I – V ) and light output power-current ( L – I ) characteristics. (a) Current–voltage (I-V) characteristics of conventional LED, LED with PQC on p-GaN surface, LED with PQC on n-side roughing, and LED with PQC structure on p-GaN surface and n-side roughing, respectively. (b) Light output power-current (L-I) and wall-plug efficiency (WPE) characteristics of LED with/without PQC structure, respectively. The light output is detected by calibrating an integrating sphere with Si photodiode on the package device. The intensity-current (L-I) characteristics of the LEDs with and without PQC structure are shown in Figure 4b.