Overview of the ATLAS Insertable B-Layer (IBL) Project

The ATLAS experiment will upgrade its Pixel Detector with the installation of a new pixel layer in 2013/14. The new subdetector, named Insertable B-Layer (IBL), will be installed between the existing Pixel Detector and a new smaller diameter beam-pipe at a radius of 33 mm. To cope with the high radiation and hit occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed and are currently under investigation and production for the IBL. Furthermore, the physics performance should be improved through the reduction of pixel size whereas targeting for a low material budget, pushing for a new mechanical support using lightweight staves and a CO2 based cooling system. An overview of the IBL project, the results of beam tests on different sensor technologies, as well as current production flow and first test results with production staves will be given.