An imaging device is provided with an imaging element. The foot splint includes a footplate for supporting the wearer’s foot, a lateral strut extending along the lower leg of the wearer and having a strap for releaseably attaching the strut to the wearer’s leg, and a wrap for wrapping around the foot of the wearer. A first dry etching is performed to remove part of the second material layer to form a first spacer by the first element and to form a second side wall by the second element, so that the first material layer between the first spacer and the second side wall is exposed to become a damaged first material layer. In one construction, the core circuit operates at 1.