The ATLAS Pixel Insertable B-Layer (IBL)

The upgrade for the ATLAS Detector will undergo di erent phases towards sLHC. The first upgrade for the Pixel Detector will consist in the construction of a new pixel layer which will be installed during a long shutdown of the LHC machine, the so-called Phase I Upgrade. The new detector, called Insertable B-Layer (IBL), will be inserted at a radius of about 3.2 cm between the existing pixel detector and a new (smaller radius) beam-pipe. The IBL requires the development of several new technologies to cope with the increased radiation level and pixel occupancy, as well as to improve the physics performance of the existing pixel detector. The IBL project is also a first step towards the Phase II upgrade of the entire ATLAS tracker and therefore will examine some of the aspects to be covered for a new pixel detector for luminosities around 10^35 cm^-2s^1. An overview of the project with particular emphasis on the IBL layout and expected performance as well as the module development including hybridization technologies is presented.