An integrated circuit device is provided including an integrated circuit substrate having a fuse region. A window layer is provided on the integrated circuit substrate that defines a fuse region. The window layer is positioned at an upper portion of the integrated circuit device and recessed beneath a surface of the integrated circuit device. A buffer pattern is provided between the integrated circuit substrate and the window layer and a fuse pattern is provided between the buffer pattern and the window layer. Methods of forming integrated circuit devices are also described.