{"id":94,"date":"2022-01-04T13:50:49","date_gmt":"2022-01-04T05:50:49","guid":{"rendered":"https:\/\/www.eee.hku.hk\/microLED\/?p=94"},"modified":"2022-01-04T17:56:33","modified_gmt":"2022-01-04T09:56:33","slug":"mechanism-of-enhanced-light-output-efficiency-in-ingan-based-microlight-emitting-diodes","status":"publish","type":"post","link":"https:\/\/www.eee.hku.hk\/microLED\/mechanism-of-enhanced-light-output-efficiency-in-ingan-based-microlight-emitting-diodes\/","title":{"rendered":"Mechanism of enhanced light output efficiency in InGaN-based microlight emitting diodes"},"content":{"rendered":"\n<p class=\"has-text-align-right\">&#8211; <em>HW Choi, CW Jeon, MD Dawson, PR Edwards, RW Martin<\/em>, and S Tripathy<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1021\" height=\"1024\" src=\"https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/2003_JAP_93_5978_image-1021x1024.png\" alt=\"\" class=\"wp-image-95\" srcset=\"https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/2003_JAP_93_5978_image-1021x1024.png 1021w, https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/2003_JAP_93_5978_image-300x300.png 300w, https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/2003_JAP_93_5978_image-150x150.png 150w, https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/2003_JAP_93_5978_image-768x770.png 768w, https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/2003_JAP_93_5978_image-299x300.png 299w, https:\/\/www.eee.hku.hk\/microLED\/wp-content\/uploads\/2022\/01\/2003_JAP_93_5978_image.png 1024w\" sizes=\"auto, (max-width: 1021px) 100vw, 1021px\" \/><figcaption>Optical image of several 12 \u00b5m microLED elements excited by a defocused 40 \u00b5m e-beam.<\/figcaption><\/figure>\n\n\n\n<p><strong>Journal of Applied Physics, vol. 93, 10, pp. 5978 (2003)<\/strong><\/p>\n\n\n\n<p>Micro-light emitting diode (LED) arrays with diameters of 4 to 20 \u03bcm have been fabricated and were found to be much more efficient light emitters compared to their broad-area counterparts, with up to five times enhancement in optical power densities. The possible mechanisms responsible for the improvement in performance were investigated. Strain relaxation in the microstructures as measured by Raman spectroscopy was not observed, arguing against theories of an increase in internal quantum efficiency due to a reduction of the piezoelectric field put forward by other groups. Optical microscope images show intense light emission at the periphery of the devices, as a result of light scattering off the etched sidewalls. This increases the extraction efficiency relative to broad area devices and boosts the forward optical output. In addition, spectra of the forward emitted light reveal the presence of resonant cavity modes [whispering gallery (WG) modes in particular] which appear to play a role in enhancing the optical output.<\/p>\n\n\n\n<p>DOI: <a href=\"https:\/\/doi.org\/10.1063\/1.1567803\" data-type=\"URL\" data-id=\"https:\/\/doi.org\/10.1063\/1.1567803\">10.1063\/1.1567803<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>&#8211; HW Choi, CW Jeon, MD Dawson, PR Edwards, RW Martin, and S Tripathy Journal of Applied Physics, vol. 93, 10, pp. 5978 (2003) Micro-light&hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[6,4,8],"class_list":["post-94","post","type-post","status-publish","format-standard","hentry","category-publications","tag-light-extraction","tag-microled","tag-monolithic"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/posts\/94","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/comments?post=94"}],"version-history":[{"count":2,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/posts\/94\/revisions"}],"predecessor-version":[{"id":166,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/posts\/94\/revisions\/166"}],"wp:attachment":[{"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/media?parent=94"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/categories?post=94"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.eee.hku.hk\/microLED\/wp-json\/wp\/v2\/tags?post=94"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}