{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T01:01:28Z","timestamp":1790298088534,"version":"4.1.0"},"reference-count":58,"publisher":"SPIE-Intl Soc Optical Eng","issue":"04","funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["EB026267"],"award-info":[{"award-number":["EB026267"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["EB019526"],"award-info":[{"award-number":["EB019526"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["EB024849"],"award-info":[{"award-number":["EB024849"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["EB025300"],"award-info":[{"award-number":["EB025300"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Med. Imag."],"published-print":{"date-parts":[[2018,10,30]]},"abstract":"<jats:p>Photon counting detectors (PCD) have the potential to improve x-ray imaging; however, they are still hindered by high costs and performance limitations. By using amorphous selenium (a-Se), the cost of PCDs can be significantly reduced compared with modern crystalline semiconductors, and enable large-area deposition. We are developing a direct conversion field-shaping multiwell avalanche detector (SWAD) to overcome the limitation of low carrier mobility and low charge conversion gain in a-Se. SWAD\u2019s dual-grid design creates separate nonavalanche interaction (bulk) and avalanche sensing (well) regions, achieving depth-independent avalanche gain. Unipolar time differential (UTD) charge sensing, combined with tunable avalanche gain in the well region allows for fast response and high charge gain. We developed a probability-based numerical simulation to investigate the impact of UTD charge sensing and avalanche gain on the photon counting performance of different a-Se detector configurations. Pulse height spectra (PHS) for 59.5 and 30\u00a0keV photons were simulated. We observed excellent agreement between our model and previously published PHS measurements for a planar detector. The energy resolution significantly improved from 33\u00a0keV for the planar detector to \u223c7\u2009\u2009keV for SWAD. SWAD was found to have a linear response approaching 200\u2009\u2009kcps\u2009\u2009\/\u2009\u2009pixel.<\/jats:p>","DOI":"10.1117\/1.jmi.5.4.043502","type":"journal-article","created":{"date-parts":[[2018,10,30]],"date-time":"2018-10-30T05:26:31Z","timestamp":1540877191000},"page":"1-11","source":"Crossref","is-referenced-by-count":11,"title":["Photon counting performance of amorphous selenium and its dependence on detector structure"],"prefix":"10.1117","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2224-2487","authenticated-orcid":false,"given":"Jann","family":"Stavro","sequence":"first","affiliation":[{"name":"Stony Brook Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amir H.","family":"Goldan","sequence":"additional","affiliation":[{"name":"Stony Brook Univ."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Zhao","sequence":"additional","affiliation":[{"name":"Stony Brook Medicine"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"189","reference":[{"key":"r1","doi-asserted-by":"publisher","DOI":"10.1118\/1.4820371"},{"key":"r2","doi-asserted-by":"publisher","DOI":"10.1063\/1.1662918"},{"key":"r3","doi-asserted-by":"publisher","DOI":"10.1088\/0031-9155\/30\/6\/002"},{"key":"r4","doi-asserted-by":"publisher","DOI":"10.1118\/1.3148535"},{"key":"r5","doi-asserted-by":"publisher","DOI":"10.1016\/j.nima.2017.07.044"},{"key":"r6","doi-asserted-by":"publisher","DOI":"10.1016\/j.ejrad.2006.08.004"},{"key":"r7","doi-asserted-by":"publisher","DOI":"10.1002\/mp.2017.44.issue-7"},{"key":"r8","doi-asserted-by":"publisher","DOI":"10.1002\/mp.2017.44.issue-6"},{"key":"r9","doi-asserted-by":"publisher","DOI":"10.1097\/RLI.0000000000000246"},{"key":"r10","doi-asserted-by":"publisher","DOI":"10.1118\/1.2731032"},{"key":"r11","doi-asserted-by":"publisher","DOI":"10.1117\/12.813037"},{"key":"r12","doi-asserted-by":"publisher","DOI":"10.1148\/radiol.13131181"},{"key":"r13","doi-asserted-by":"publisher","DOI":"10.1016\/j.nima.2009.10.152"},{"key":"r14","doi-asserted-by":"publisher","DOI":"10.1117\/12.844669"},{"key":"r15","doi-asserted-by":"publisher","DOI":"10.1109\/TNS.2009.2013709"},{"key":"r16","doi-asserted-by":"publisher","DOI":"10.1109\/23.873002"},{"key":"r17","doi-asserted-by":"publisher","DOI":"10.1016\/j.nima.2018.03.006"},{"key":"r18","doi-asserted-by":"publisher","DOI":"10.1109\/TNS.2002.998748"},{"key":"r19","doi-asserted-by":"publisher","DOI":"10.1088\/1748-0221\/8\/02\/C02028"},{"key":"r20","doi-asserted-by":"publisher","DOI":"10.1109\/TNS.2011.2122267"},{"key":"r21","doi-asserted-by":"publisher","DOI":"10.1109\/TNS.2006.869843"},{"key":"r22","doi-asserted-by":"publisher","DOI":"10.1118\/1.3245875"},{"key":"r23","doi-asserted-by":"publisher","DOI":"10.1109\/TNS.2005.851419"},{"key":"r24","doi-asserted-by":"publisher","DOI":"10.1109\/TNS.2007.914034"},{"key":"r25","doi-asserted-by":"publisher","DOI":"10.1088\/0031-9155\/61\/4\/1572"},{"key":"r26","doi-asserted-by":"publisher","DOI":"10.1002\/pssb.v246:8"},{"key":"r27","doi-asserted-by":"publisher","DOI":"10.1118\/1.4770279"},{"key":"r28","doi-asserted-by":"publisher","DOI":"10.1109\/EDL.1987.26671"},{"key":"r29","doi-asserted-by":"publisher","DOI":"10.1016\/j.cap.2011.12.023"},{"key":"r30","doi-asserted-by":"publisher","DOI":"10.1109\/16.628837"},{"key":"r31","doi-asserted-by":"publisher","DOI":"10.1118\/1.4907971"},{"key":"r32","doi-asserted-by":"publisher","DOI":"10.1002\/mp.12693"},{"key":"r33","doi-asserted-by":"publisher","DOI":"10.1063\/1.4807292"},{"key":"r34","doi-asserted-by":"publisher","DOI":"10.1117\/12.594623"},{"key":"r35","doi-asserted-by":"publisher","DOI":"10.1118\/1.3002314"},{"key":"r36","doi-asserted-by":"publisher","DOI":"10.1118\/1.4769110"},{"key":"r37","article-title":"British atomic energy report","author":"Frisch","year":"1944"},{"key":"r38","doi-asserted-by":"publisher","DOI":"10.1118\/1.2335491"},{"key":"r39","doi-asserted-by":"publisher","DOI":"10.1117\/12.2255733"},{"key":"r40","doi-asserted-by":"publisher","DOI":"10.1063\/1.370615"},{"key":"r41","doi-asserted-by":"publisher","DOI":"10.1117\/12.878134"},{"key":"r42","doi-asserted-by":"publisher","DOI":"10.1116\/1.1460900"},{"key":"r43","doi-asserted-by":"publisher","DOI":"10.1063\/1.1710367"},{"key":"r44","doi-asserted-by":"publisher","DOI":"10.1109\/JRPROC.1939.228757"},{"key":"r45","doi-asserted-by":"publisher","DOI":"10.1088\/0022-3727\/33\/4\/320"},{"key":"r46","doi-asserted-by":"publisher","DOI":"10.1063\/1.110393"},{"key":"r47","doi-asserted-by":"publisher","DOI":"10.1103\/PhysRevB.12.2455"},{"key":"r48","doi-asserted-by":"publisher","DOI":"10.1080\/00018737800101474"},{"key":"r49","doi-asserted-by":"publisher","DOI":"10.1088\/1748-0221\/11\/01\/P01007"},{"key":"r50","doi-asserted-by":"publisher","DOI":"10.1117\/12.710358"},{"key":"r51","doi-asserted-by":"publisher","DOI":"10.1117\/12.770766"},{"key":"r52","doi-asserted-by":"publisher","DOI":"10.1117\/12.2217248"},{"key":"r53","doi-asserted-by":"publisher","DOI":"10.1118\/1.3673957"},{"key":"r54","doi-asserted-by":"crossref","DOI":"10.1109\/IEDM.2015.7409803","article-title":"High dose efficiency, ultra-high resolution amorphous selenium\/CMOS hybrid digital X-ray imager","author":"Scott","year":"2015"},{"key":"r55","first-page":"279","article-title":"Ultra high resolution digital xeroradiography for x-ray microscopic detector","author":"Oguro","year":"1989"},{"key":"r56","doi-asserted-by":"publisher","DOI":"10.1103\/PhysRevLett.75.156"},{"key":"r57","doi-asserted-by":"publisher","DOI":"10.1117\/12.813361"},{"key":"r58","doi-asserted-by":"publisher","DOI":"10.1016\/j.nima.2017.05.010"}],"container-title":["Journal of Medical Imaging"],"original-title":[],"link":[{"URL":"https:\/\/www.spiedigitallibrary.org\/journals\/journal-of-medical-imaging\/volume-5\/issue-04\/043502\/Photon-counting-performance-of-amorphous-selenium-and-its-dependence-on\/10.1117\/1.JMI.5.4.043502.full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T00:26:49Z","timestamp":1790296009000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.spiedigitallibrary.org\/journals\/journal-of-medical-imaging\/volume-5\/issue-04\/043502\/Photon-counting-performance-of-amorphous-selenium-and-its-dependence-on\/10.1117\/1.JMI.5.4.043502.full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,10,30]]},"references-count":58,"journal-issue":{"issue":"04"},"URL":"https:\/\/doi.org\/10.1117\/1.jmi.5.4.043502","relation":{},"ISSN":["2329-4302","2329-4310"],"issn-type":[{"value":"2329-4302","type":"print"},{"value":"2329-4310","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,10,30]]}}}