{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T21:55:54Z","timestamp":1774475754658,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,7,19]],"date-time":"2021-07-19T00:00:00Z","timestamp":1626652800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Trade, Industry &amp; Energy, GNU-Samsung Display Center","award":["MOTIE, No. 20010464"],"award-info":[{"award-number":["MOTIE, No. 20010464"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>We investigated the performance of single-structured light-emitting electrochemical cell (LEC) devices with Ru(bpy)3(PF6)2 polymer composite as an emission layer by controlling thickness and heat treatment. When the thickness was smaller than 120\u2013150 nm, the device performance decreased because of the low optical properties and non-dense surface properties. On the other hand, when the thickness was over than 150 nm, the device had too high surface roughness, resulting in high-efficiency roll-off and poor device stability. With 150 nm thickness, the absorbance increased, and the surface roughness was low and dense, resulting in increased device characteristics and better stability. The heat treatment effect further improved the surface properties, thus improving the device characteristics. In particular, the external quantum efficiency (EQE) reduction rate was shallow at 100 \u00b0C, which indicates that the LEC device has stable operating characteristics. The LEC device exhibited a maximum luminance of 3532 cd\/m2 and an EQE of 1.14% under 150 nm thickness and 100 \u00b0C heat treatment.<\/jats:p>","DOI":"10.3390\/mi12070843","type":"journal-article","created":{"date-parts":[[2021,7,19]],"date-time":"2021-07-19T21:39:15Z","timestamp":1626730755000},"page":"843","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Effect of Optical and Morphological Control of Single-Structured LEC Device"],"prefix":"10.3390","volume":"12","author":[{"given":"Woo Jin","family":"Jeong","sequence":"first","affiliation":[{"name":"Department of Semiconductor Engineering, Gyeongsang National University, 501 Jinjudaero, Jinju 52828, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jong Ik","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hee Jung","family":"Kwak","sequence":"additional","affiliation":[{"name":"Department of Semiconductor Engineering, Gyeongsang National University, 501 Jinjudaero, Jinju 52828, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jae Min","family":"Jeon","sequence":"additional","affiliation":[{"name":"Department of Semiconductor Engineering, Gyeongsang National University, 501 Jinjudaero, Jinju 52828, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dong Yeol","family":"Shin","sequence":"additional","affiliation":[{"name":"Department of Semiconductor Engineering, Gyeongsang National University, 501 Jinjudaero, Jinju 52828, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Moon Sung","family":"Kang","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Korea"},{"name":"Institute of Emergent Materials, Sogang University, Seoul 04107, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0641-4891","authenticated-orcid":false,"given":"Jun Young","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Semiconductor Engineering, Gyeongsang National University, 501 Jinjudaero, Jinju 52828, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"572","DOI":"10.1002\/pi.1974","article-title":"Organic Light-Emitting Diode (OLED) Technology: Materials, Devices and Display Technologies","volume":"55","author":"Geffroy","year":"2006","journal-title":"Polym. 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