{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T18:17:12Z","timestamp":1774981032090,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2023,8,16]],"date-time":"2023-08-16T00:00:00Z","timestamp":1692144000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Nature Science Foundation of Anhui Province","award":["2208085MF176"],"award-info":[{"award-number":["2208085MF176"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Near-infrared (NIR) photodetectors (PDs) have attracted much attention for use in noninvasive medical diagnosis and treatments. In particular, self-filtered NIR PDs are in high demand for a wide range of biomedical applications due to their ability for wavelength discrimination. In this work, we designed and then fabricated a Si micro-hole array\/Graphene (Si MHA\/Gr) van der Waals (vdW) Schottky NIR photodiode using a PbS quantum dot (QD) coating. The device exhibited a unique self-filtered NIR response with a responsivity of 0.7 A\/W at \u22121 V and a response speed of 61 \u03bcs, which is higher than that seen without PbS QD coating and even in most previous Si\/Gr Schottky photodiodes. The light trapping of the Si MHA and the PbS QD coating could be attributed to the high responsivity of the vdW photodiode. Furthermore, the presented NIR photodiode could also be integrated in photoplethysmography (PPG) for real-time heart rate (HR) monitoring. The extracted HR was in good accord with the values measured with the patient monitor\u2014determined by analyzing the Fourier transform of the stable and reliable fingertip PPG waveform\u2014suggesting its potential for practical applications.<\/jats:p>","DOI":"10.3390\/s23167214","type":"journal-article","created":{"date-parts":[[2023,8,17]],"date-time":"2023-08-17T10:47:02Z","timestamp":1692269222000},"page":"7214","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["PbS QD-Coated Si Micro-Hole Array\/Graphene vdW Schottky Near-Infrared Photodiode for PPG Heart Rate Measurement"],"prefix":"10.3390","volume":"23","author":[{"given":"Mingyuan","family":"Xu","sequence":"first","affiliation":[{"name":"School of Advanced Manufacturing, Nanchang University, Nanchang 330031, China"}]},{"given":"Yinghao","family":"Cui","sequence":"additional","affiliation":[{"name":"School of Microelectronics, Micro Electromechanical System Research Center of Engineering and Technology of Anhui Province, Hefei University of Technology, Hefei 230009, China"}]},{"given":"Tao","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Microelectronics, Micro Electromechanical System Research Center of Engineering and Technology of Anhui Province, Hefei University of Technology, Hefei 230009, China"}]},{"given":"Mengxue","family":"Lu","sequence":"additional","affiliation":[{"name":"School of Microelectronics, Micro Electromechanical System Research Center of Engineering and Technology of Anhui Province, Hefei University of Technology, Hefei 230009, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6949-0592","authenticated-orcid":false,"given":"Yongqiang","family":"Yu","sequence":"additional","affiliation":[{"name":"School of Microelectronics, Micro Electromechanical System Research Center of Engineering and Technology of Anhui Province, Hefei University of Technology, Hefei 230009, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5586","DOI":"10.1021\/acs.nanolett.1c01081","article-title":"Single-dislocation Schottky diodes","volume":"21","author":"Tao","year":"2021","journal-title":"Nano Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1801182","DOI":"10.1002\/smll.201801182","article-title":"Gate-controlled graphene\u2013silicon Schottky junction photodetector","volume":"14","author":"Chang","year":"2018","journal-title":"Small"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1808182","DOI":"10.1002\/adfm.201808182","article-title":"Silicon-compatible photodetectors: Trends to monolithically integrate photosensors with chip technology","volume":"29","author":"Yang","year":"2019","journal-title":"Adv. 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