The enthusiasm towards flexible single crystal silicon electronics and photonics is stimulated by a natural quandary: the well-established integrated electronics and photonics are manufactured on silicon based substrates,which are rigid;on the contrary,all organisms are soft and curvilinear.This seemingly intrinsic incompatibility is resolved by the discovery that inorganic nanomembranes with thickness less than a few hundred nanometers can have flexural rigidities more than fifteen orders of magnitude smaller than those of bulk wafers(>200 μm)of the same materials.[l] A hybrid platform which enjoys both the high performance of inorganic materials and the flexibility of organic materials is believed to have a vast range of unprecedented applications which could not be implemented by either inorganic or organic platforms alone.However,the difficulty in transferring intricate silicon photonic devices has deterred widespread development.In this paper,we present a high yield transfer method exploiting wafer bonding and substrate removal.[2][3] With this method,a single crystal silicon nanomembrane photonic crystal microcavity,with feature sizes ranging from 80 nm to 6 ram,is successfully transferred onto a polyimide film.The transferred cavity shows a quality factor of 2.2× 104,and could be bended to a curvature of 5 mm radius without deteriorating the performance compared to its counterparts on rigid substrates.[2] A thorough characterization of the device reveals that the resonant wavelength is a linear function of the bending-induced strain.The device also shows a curvature-independent sensitivity to the ambient index variation.This demonstration paves the way to an entirely new category of silicon photonics devices which can be used for a vast range of unprecedented applications including epidermal health monitors,conformal strain sensors,implantable sensors,etc.