Cost-effective layer transfer by controlled spalling technology

Although historically studied as a failure mode, substrate spalling can be transformed into a versatile layer transfer method by carefully controlling the thickness and intrinsic stress of a surface layer, and mechanically guiding the fracture path. This Controlled Spalling process requires no specialized equipment and can be applied to essentially any brittle substrate. We have successfully demonstrated i) device fabrication in Si, Ge, and III-V based materials, ii) removal of fully-processed CMOS circuits, iii) kerffree ingot slicing, iv) 300 mm diameter layer transfer and v) a wide range of other materials such as GaN grown on sapphire. © The Electrochemical Society.