NOVELTY - Control of temperature during cleaving of free-standing thick films from bulk material comprises clamping bulk material to engage through seal to form cavity; sensing state of bulk material to generate input data; maintaining temperature of surface region by processing input data; and executing control scheme using particle bombardment to heat surface region, radiation to heat surface region, and/or gas-assisted conduction between bottom region and stage.    USE - Control of temperature during cleaving of free-standing thick films used as photovoltaic material, e.g. solar cells. Uses include but are not limited to three-dimensional packaging of integrated semiconductor devices, photonic devices, piezoelectronic devices, flat panel displays, microelectromechanical systems (MEMS), nano-technology structures, sensors, actuators, integrated circuits, or semiconductor substrate manufacturing, biological and bio-medical devices.    ADVANTAGE - The method uses cost effective linear accelerator device and method for providing high energy implant process for layer transfer techniques.    DETAILED DESCRIPTION - Control of temperature during cleaving of free-standing thick films from bulk material comprises providing bulk material for cleaving; clamping bulk material using mechanical clamp device to engage bottom region of bulk material through seal with planar surface of stage to form cavity with height between bottom region and planar surface, in which planar surface comprises gas passageways allowing gas filled in cavity with adjustable pressure; sensing state of bulk material to generate input data including temperature information at surface region and bottom region and length of bulk material between surface region and bottom region; maintaining temperature of surface region by processing input data; and executing control scheme using particle bombardment to heat surface region, radiation to heat surface region, and/or gas-assisted conduction between bottom region and stage. The method also comprises inductive heating bulk material in control scheme. The bulk material is preprocessed to planarize surface region for facilitating cleaving process. The clamping of bulk material is performed such that surface region and at least 70% of bulk material from surface region are exposed for cleaving thick films without interference of clamp device. The stage is electrostatic chuck capable of generating electrostatic force to attract bulk material. The surface region of bulk material is repaired at least by one of ion particle bombardment, etching, or depositing smooth layer on surface region. The radiation used for heating surface region comprising using external radiant heat source located above surface region. The radiant heat source comprises several flash lamps with controlled power supply, pulse rate, and spatial distribution. The cavity height may be 3-200 mu m. The cleaving process comprises introducing first particles at less than 250 degrees C to form defect region within vicinity of cleave region and introducing second particles at 250-550 degrees C into defect to cause increase of stress of cleave region from first value to second value. It further comprises repeatedly producing free-standing thick films of bulk material with thickness of 15-200 mu m. It can be thermal cleaving process or controlled cleaving process utilizing vertical thermal gradient to remove film. It further comprises performing surface treatment on free-standing thick film to remove surface cracks and reduce surface roughness of remaining bulk material. The particles are provided at 1-5 MeV using linear accelerator process comprising radio frequency quadruple elements and/or drift tube linear accelerator elements to confine and accelerate particles. The method further comprises thermal treatment at greater than or equal to 400 degrees C to render defect region to be close to cleave region and stabilize defect region.