US 12,336,326 B2
Method of manufacturing micro devices
Li-Yi Chen, Tainan (TW); and Hsiao-Fu Lu, Tainan (TW)
Assigned to MIKRO MESA TECHNOLOGY CO., LTD., Apia (WS)
Filed by MIKRO MESA TECHNOLOGY CO., LTD., Apia (WS)
Filed on Jun. 12, 2022, as Appl. No. 17/806,499.
Prior Publication US 2023/0402565 A1, Dec. 14, 2023
Int. Cl. H10H 20/01 (2025.01)
CPC H10H 20/0137 (2025.01) [H10H 20/01 (2025.01)] 14 Claims
OG exemplary drawing
 
1. A method of manufacturing micro devices, comprising:
preparing a GaN-based epitaxial structure attached on a substrate, the GaN-based epitaxial structure comprising a p-type GaN layer, a n-type GaN layer on the p-type GaN layer, and an undoped GaN layer on the n-type GaN layer;
forming a photoresist layer on the GaN-based epitaxial structure with the undoped GaN layer contacting the photoresist layer;
patterning the photoresist layer to expose portions of the undoped GaN layer;
performing a plasma etching process to the GaN-based epitaxial structure through the patterned photoresist layer until the patterned photoresist layer is completely removed and the undoped GaN layer is patterned, such that a plurality of mesas are formed on the etched GaN-based epitaxial structure, wherein a height of the mesas is at least 1.0 μm; and
continuing to perform the plasma etching process using the patterned undoped GaN layer as an etching mask until the patterned undoped GaN layer is completely removed to expose the n-type GaN layer and the etched GaN-based epitaxial structure is cut into a plurality of micro devices.