Patterning GaN Microstructures by Polarity-Selective Chemical Etching

The study of wet etching on GaN surface by potassium hydroxide solution

“…We can also observe in Fig. 5 that the sidewall of the a-plane (11)(12)(13)(14)(15)(16)(17)(18)(19)(20) should only be formed by etching the inclined plane of the a-plane (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22) first.…”

“…Overall, we propose a complete and reasonable mechanism for the etching behavior of the whole KOH etching on GaN, and the experimental result is consistent with our theory. 5 The diagram of the shrinkage motion for (10-1-1) and (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22) The study of wet etching on GaN surface by potassium……”

“…For example, Dongsheng Li et al [15] processed etching and studied etching behavior with the ratio of KOH:H 2 O = 1:5 at room temperature at different times (3,30, and 70 min). Moreover, Ng et al [16] discussed the etching behavior of the Ga-polar GaN and that of the N-polar GaN at different etching times (30-60 min) with KOH concentration of 2-4 M and temperature at 100°C.…”

Fabrication of microrods and microtips of InP by electrochemical etching

“…Now many techniques have been employed to fabricate semiconductor microstructure, like metal-organic chemical vapor deposition [1][2][3][4][5], molecular beam epitaxy [6], liquid-phase epitaxy [7] and electrochemical techniques [8][9][10][11][12][13][14][15][16]. Among these techniques the electrochemical techniques have their own advantages, such as their low processing temperature, low damage, low-cost and versatility.…”

“…Many microstructures have been fabricated by electrochemical techniques in the last decade. For instance, the microtips of Si [8,9] and GaN [10,11] and the microrods (whiskers) of GaN [12] were fabricated in KOH solutions. The microtips of InP were gotten in strong HCl solutions [13] and in the ternary HBr-K 2 Cr 2 O 7 -H 2 O solutions [14].…”