A tiled detector assembly (1000) and a method for making a tiled radiation detector (1000) is described. The innovative feature of this method is that the xyz misalignment of the detector tiles (304, 304′), the origin of various image artifacts, can be significantly reduced by accurate sizing and alignment of the detector tiles (304, 304′). Consequently, image quality, yield and reliability of as-produced tiled radiation detectors are considerably improved.