Chapter 5: WFC3 Detector Characteristics and Performance 5.1 Overview of this Chapter 5.2 The WFC3 UVIS Channel CCD Detectors 5.2.1 Basics of CCD Operation 5.2.2 The WFC3 CCDs 5.3 WFC3 CCD Readout Formats 5.3.1 Full-frame Readout 5.3.2 Subarrays 5.3.3 On-Chip Binning 5.4 WFC3 CCD Characteristics and Performance 5.4.1 Quantum Efficiency 5.4.2 Multiple-Electron Events at Short Wavelengths 5.4.3 Flat Fields 5.4.4 Long-Wavelength Fringing 5.4.5 Linearity and Saturation 5.4.6 Gain 5.4.7 Read Noise 5.4.8 Dark Current 5.4.9 Bad Pixels 5.4.10 Cosmic Rays 5.4.11 Charge Transfer Efficiency 5.4.12 Crosstalk 5.5 The WFC3 IR Channel Detector 5.5.1 Overview 5.5.2 IR Detector Basics 5.6 WFC3 IR Readout Formats 5.6.1 Full-Frame Readouts and Reference Pixels 5.6.2 Subarrays 5.7 WFC3/IR Detector Characteristics and Performance 5.7.1 Quantum Efficiency 5.7.2 Dark Current 5.7.3 Read Noise 5.7.4 Flat Fields 5.7.5 Linearity and Saturation 5.7.6 Count Rate Non-Linearity 5.7.7 Detector Cosmetics 5.7.8 Crosstalk