The　reduction　in　the　display　chip　size　of　micro　light　emitting　diode　(Micro-LED)　exerts　a　sidewall　effect　and　consequently　results　in　a　decreased　forward　light　extraction　efficiency　(LEE).　The　display　chip　structure　of　Micro-LED　with　high　LEE　still　needs　to　be　further　studied.　For　this　reason,　an　optimized　model　of　GaN-based　Micro-LED　with　high　LEE　is　explored　by　leveraging　the　finite-difference　time-domain　method　from　a　simulation　perspective.　Specifically,　the　initial　laminated　structure　of　GaN-based　Micro-LED　with　vertical　sidewalls　is　constructed,　and　the　influence　of　the　sidewall　effect　on　LEE　is　analyzed　quantitatively.　Then,　the　impact　of　the　position　change　of　multiple-quantum-well　active　layer　in　Micro-LED　on　the　light　output　effect　is　investigated,　and　Micro-LED　structure　models　with　different　inclined　sidewall　angles　are　analyzed.　The　influence　of　the　bottom　reflective　material　on　LEE　is　discussed,　and　the　parameters　of　the　preliminarily　optimized　GaN-based　Micro-LED　model　are　obtained.　Finally,　LEE　is　further　improved　by　designing　a　top　transmission　grating,　and　the　effects　of　period,　height,　and　duty　cycle　on　LEE　are　examined.　The　results　show　that　the　overall　LEE　of　the　optimized　GaN-based　Micro-LED　is　2.42　times　higher　than　that　of　the　initial　structure.　©　2022,　Chinese　Lasers　Press.　All　right　reserved.