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Silicon Thin Film Transistor Based on Pbs Nano-Particles : an Efficient Phototransistor for the Detection of Infrared Light Xiang Liu

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Silicon Thin Film Transistor Based on Pbs Nano-Particles : an Efficient Phototransistor for the Detection of Infrared Light Xiang Liu Silicon thin film transistor based on PbS nano-particles : an efficient phototransistor for the detection of infrared light Xiang Liu To cite this version: Xiang Liu. Silicon thin film transistor based on PbS nano-particles : an efficient phototransistor for the detection of infrared light. Micro and nanotechnologies/Microelectronics. Université de Rennes1, 2016. English. tel-02441354 HAL Id: tel-02441354 https://hal.archives-ouvertes.fr/tel-02441354 Submitted on 15 Jan 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. ANNÉE (2016) THÈSE / UNIVERSITÉ DE RENNES 1 sous le sceau de l’Université Bretagne Loire en Cotutelle Internationale avec UNIVERSITÉ du SUD-EST (SOUTHEAST UNIVERSITY), NANJING, CHINE pour le grade de DOCTEUR DE L’UNIVERSITÉ DE RENNES 1 Mention : (Electronique) Ecole doctorale (MATISSE) présentée par Xiang LIU préparée à l'unité de recherche IETR- UMR CNRS 6164 Institut d'Electronique et de Télécommunication de Rennes UFR Informatique – Electronique et au Display Center, School of Electronic Science and Engineering, Southeast University Thèse soutenue à Nanjing (Chine) Intitulé de la thèse : le 27 décembre 2016 devant le jury composé de : Transistor silicium en Olivier DURAND Professeur, INSA Rennes / rapporteur couche mince à base Li LI de nano-particules de Professeur, Nanjing University of Science and Technology, Chine / rapporteur PbS : Un efficace Emmanuel JACQUES Maître de Conférences, Université Rennes 1 / phototransistor pour la examinateur Qing LI détection de lumière Professeur, South-East University Nanjing, Chine / infrarouge. examinateur Wei LEI Professeur, South-East University Nanjing, Chine / co- directeur de thèse Tayeb MOHAMMED-BRAHIM Professeur Université Rennes 1 / directeur de thèse Table of content Table of Content Introduction .................................................................................................................. 7 Chapter 1 Quantum dots based NIR Phototransistor: application and fabrication ..................................................................................................................................... 10 1. Introduction .................................................................................................................... 11 2. State-of-the-arts of Infrared photodetector ................................................................ 12 2.1 HdCdTe Infrared photodetector ................................................................................ 13 2.2 Quantum well Infrared photodetector ....................................................................... 14 2.3 Strained superlattices Infrared photodetector ........................................................... 15 2.4 Quantum dots Infrared photodetector ....................................................................... 15 3. Theory and mechanism of photodetection .................................................................. 19 3.1 The theory of photoconductivity ............................................................................... 19 3.2 The main parameters of a photodetector ................................................................... 20 4. Main Photodetectors ..................................................................................................... 23 4.1 Photoconductors ....................................................................................................... 23 4.2 Photodiode ................................................................................................................ 23 4.2 Phototransistor .......................................................................................................... 23 5. Reviews of phototransistors ......................................................................................... 24 5.1 Silicon-based MOS phototransistor .......................................................................... 24 5.2 Oxide-base phototransistors ...................................................................................... 26 5.3 Phototransistor with QDs’ hybrid active layer .......................................................... 28 Table of content 5.4 Phototransistor with QDs’ hybrid insulator .............................................................. 30 6. Conclusion...................................................................................................................... 32 7. Reference ........................................................................................................................ 33 Chapter 2 Fabrication technology and electrical characterization of Poly-silicon Thin Film Transistor .................................................................................................. 44 1. Introduction ................................................................................................................... 45 2. Fabrication Process of Thin Film Transistor .............................................................. 45 2.1 Undoped poly-silicon active layer deposition by LPCVD ....................................... 46 2.2 Doped poly-silicon deposition for drain/source region ............................................ 48 2.3 Definition of TFT’s channel and geometry ............................................................... 48 2.4 RCA cleaning of the as-prepared device ................................................................... 49 2.5 Gate insulator deposition .......................................................................................... 50 2.5.1 SiO2 inorganic insulator deposition ................................................................................. 50 2.5.2 SU8 organic insulator deposition .................................................................................... 53 2.6 Gate insulator etching for drain/source contact ........................................................ 56 2.6.1 Wet-etching on inorganic SiO2 insulator ......................................................................... 57 2.6.2 Dry-etching on organic SU8 insulator ............................................................................. 57 2.7 Transparent AZO (ZnO:AL) electrode depostition by RF sputtering and the etching process for Source/Gate/Drain formation ....................................................................... 58 3. Operating principle and performance for the Poly-silicon TFT ............................... 59 3.1 Device physics for TFTs ........................................................................................... 60 Table of content 3.2 TFTs’ electrical parameters characterization of typical SiO2 gated TFTs ................. 64 3.3 TFTs’ electrical parameters characterization of Organic SU8 gated TFTs ............... 66 4. Conclusion...................................................................................................................... 68 5. Reference ........................................................................................................................ 69 Chapter 3 Synthesis and Characterization of Quantum dots ................................ 73 1. Introduction ................................................................................................................... 74 2. QDs’ properties and synthesis mechanism .................................................................. 75 2.1 QDs’ properties ......................................................................................................... 75 2.2 QDs’ synthesis mechanism ....................................................................................... 76 2.3 QDs’ carrier’s transport mechanism ......................................................................... 79 2.4 Characterization method and instrument of QDs ...................................................... 82 2.5 QDs’ application in optoelectronics .......................................................................... 84 3. Synthesis details of PbS QDs ........................................................................................ 86 3.1 Materials and instruments for experiment ................................................................ 87 3.2 Synthesis process for PbS QDs ................................................................................. 87 4. Characterization of Infrared-PbS QDs ....................................................................... 88 5. Ligand exchange experiments of QDs ......................................................................... 91 5.1 ligands of QDs .......................................................................................................... 91 5.2 ligands’s exchange experiment of QDs .................................................................... 92 5.1 Simulation and Characterization of QDs encapsulated with different ligand ........... 94 6. Characterization of PbS QDs and QDs/SU8 hybrid material ................................... 97 Table of content 7. Conclusion.....................................................................................................................
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