Abstract
List of Figures viii
List of Tables xvi
List of Abbreviations xviii
1 Introduction 1
1.1 The Universe and Dark Matter.................................................................. 1
1.1.1 Evidence of dark matter........................................................................ 2
1.1.1.1 Not enough visible matter........................................................ 4
1.1.1.2 Gravitational lensing ............................................................... 5
1.2 Direct detection of DM................................................................................. 6
1.2.1 Direct detection signals........................................................................ 9
2 Solid state devices 11
2.1 Solid state physics........................................................................................... 11
2.1.1 Quantum potential well........................................................................ 13
2.1.2 Semiconductor........................................................................................ 16
2.1.3 The P-N junction ................................................................................. 17
2.1.4 Diodes....................................................................................................... 19
2.1.5 Transistor................................................................................................. 20
2.2 CCDs.................................................................................................................... 21
2.2.1 Capacitative-coupled section: Gates and pixel.................................... 22
2.2.2 Transporting channel ............................................................................ 25
2.2.3 Readout component............................................................................... 26
3 Radiation damage 29
3.1 Damage mechanism incrystals.................................................................... 30
3.1.1 After collision with an lattice atom...................................................... 32
3.1.2 Defect production.................................................................................. 34
3.2 Effects of damage........................................................................................... 36
3.3 Defect identification andmitigation............................................................ 38
3.3.1 Thermal Stimulation Current (TSC) Analysis................................... 38
3.3.2 Deep Level Transient Spectroscopy (DLTS)...................................... 39
3.3.3 Defect recovery........................................................................................ 42
4 Dark Matter In CCDs 44
4.1 DAMIC CCDs................................................................................................. 46
4.2 DAMIC CCD Operations........................................................................... 50
4.2.1 Unbinned lxl images ........................................................................... 53
4.2.2 Binned 1x100 images............................................................................... 55
4.3 Image processing.............................................................................................. 57
4.3.1 Noise control and calibration............................................................... 57
4.3.2 Particle tracks separation and categorization ................................... 59
4.4 Dark Matter Searches usingionization.................................................... 63
4.4.1 DAMIC-SNOLAB, pre2019.................................................................... 63
4.4.2 DAMIC-M LBC..................................................................................... 65
4.4.3 DAMIC at SNOLAB, post 2021 ............................................................ 66
5 Device simulations 68
5.1 Device setup..................................................................................................... 68
5.1.1 Substructures of the DAMIC CCDs ................................................... 68
5.2 CCD operation simulation............................................................................ 74
5.3 Simulation support for CCDs..................................................................... 77
6 Radiation Damage in CCDs 84
6.1 Defects in DAMIC-S2019.......................................................................... 86
6.1.1 Development of edge finder algorithm ............................................... 86
6.1.2 Defect identification............................................................................... 89
6.1.3 Search for defect origin ........................................................................ 90
6.2 Daily modulation of defect production due to DM in Si................ 93
6.3 Defects in SENSEI CCDs........................................................................... 95
6.4 DAMIC Diodes and mini CCDs at CERN............................................ 97
7 Neutron irradiation campaign 105
7.1 Experimental setup....................................................................................... 106
7.1.1 General Procedure................................................................................. 109
7.1.2 Defect search.......................................................................................... 110
7.1.3 55Fe calibration....................................................................................... Ill
7.1.4 Proof of concept.................................................................................... Ill
7.1.5 AmBe irradiation 1.................................................................................. 112
7.1.6 AmBe irradiation 2.................................................................................. 112
7.2 Data analysis........................................................................................................114
7.2.1 Defect identification.............................................................................. 115
7.2.2 Background.............................................................................................. 115
7.2.3 Calibration.............................................................................................. 115
7.2.4 Defect analysis....................................................................................... 118
7.2.5 Neutrons and defects.............................................................................. 132
7.3 Further irradiation ............................................................................................135
8 Conclusions 136
Appendix A DAMIC diodes and packaging details 146
A.l Probing ................................................................................................................. 146
A.2 Dicing .....................................................................................................................146
A.3 Packaging.............................................................................................................. 148
Appendix B DAMIC-M calibration system 150
Appendix C DAMIC-M cold testing jig 151
C.l Target environment............................................................................................151
C. 2 Probing or bonding........................................................................................ 151
Appendix D Irradiation Campaign Parameters 154
D. l lxl readout used for both 10 and 1 minute exposures configuration file.............................................................................................................................. 154
D.2 Clear image configuration file...................................................................... 158
D.3 6k X 4, 1000 skip calibration image configuration file...................... 163
D.4 Fe-55 calibration table for UW6418......................................................... 167
Appendix E Defect efficiency of 100 keV neutrons 169
Lee, Steven Juhyung