Title Page
Contents
ABSTRACT 8
1. Introduction 9
2. Background 12
2.1. Organic-inorganic halide perovskite semiconductor 12
2.2. Methods of growing of perovskite single crystals 13
2.3. Perovskite X-ray detector 16
3. Experimental 20
3.1. Chemicals and reagents 20
3.2. Synthesis of CsFAMAPbI₃ single crystals 20
3.3. Surface treatment and detector fabrication 20
3.4. Characterization 21
3.5. X-ray response and sensitivity measurement 21
4. Result and discussion 24
4.1. Material properties of perovskite single crystals 24
4.2. X-ray response and sensitivity 32
5. Conclusion 36
References 37
Abstract (in Korean) 43
Table 1. The average PL lifetime of CFMPI SCs with different conditions. 30
Figure 1-1. Structure of the unit cell of perovskite. 12
Figure 1-2. ITC method and growth process of the FAPbI₃ single crystal. 14
Figure 1-3. Schematic diagram of the AVC method. 15
Figure 1-4. Photographs of the CsPbBr₃ crystal grown with Bridgeman method and growth process. 16
Figure 1-5. The mechanism of X-ray detectors. (a) Current-mode detector and (b) Voltage-mode detector. 19
Figure 2-1. Schematic diagram of surface engineering process and device fabrication of samples. 24
Figure 2-2. a) XRD patterns of the CFMPI SCs before/after PEAI passivation. b, c) The enlargement of the PbI₂ and (110) peaks. d) GIXRD patterns of CFMPI SCs treated with... 25
Figure 2-3. a, b) XPS spectra of CFMPI SCs before/after PEAI treatment with different conditions. The C 1s and I 3d core-level energy spectra are shown for comparison. c)... 27
Figure 2-4. a, b) SSPL spectra and TRPL spectra of CFMPI SCs before/after PEAI passivation with different conditions. c) FLIM images of CFMPI SCs with different conditions. 29
Figure 2-5. SEM images of Control SCs and PEAI passivation with different conditions. Schematic diagram of the morphology and distribution of PEA₂PbI₄ on the surface of SCs. 30
Figure 2-6. a, b, c) Dark current density of CFMPI SCs before/after PEAI passivation with different conditions. d, e, f) Current-voltage curves for CFMPI SCs with PEAI... 31
Figure 2-7. Simulations using physical properties. 32
Figure 2-8. a, b, c) X-ray photoresponse of the sample of Control, PEAI 10s and PEAI 30s at a 20V bias and under different dose rates. d, e, f) Dose-rate-dependent... 34