A hemispherical electronic eye camera based on compressible silicon optoelectronics

Abstract

The human eye is a remarkable imaging device, with many attractive design features. Prominent among these is a hemispherical detector geometry, similar to that found in many other biological systems, that enables a wide field of view and low aberrations with simple, few-component imaging optics. This type of configuration is extremely difficult to achieve using established optoelectronics technologies, owing to the intrinsically planar nature of the patterning, deposition, etching, materials growth and doping methods that exist for fabricating such systems. Here we report strategies that avoid these limitations, and implement them to yield high-performance, hemispherical electronic eye cameras based on single-crystalline silicon. The approach uses wafer-scale optoelectronics formed in unusual, two-dimensionally compressible configurations and elastomeric transfer elements capable of transforming the planar layouts in which the systems are initially fabricated into hemispherical geometries for their final implementation. In a general sense, these methods, taken together with our theoretical analyses of their associated mechanics, provide practical routes for integrating well-developed planar device technologies onto the surfaces of complex curvilinear objects, suitable for diverse applications that cannot be addressed by conventional means.

In‐Plane Deformation Mechanics for Highly Stretchable Electronics

“…[13,14] A key challenge in each of these systems is in the development of strategies in mechanics that simultaneously allow large levels of elastic stretchability and high areal coverages of active devices built with materials that are themselves not stretchable (e.g., conventional metals) and are, in some cases, highly brittle (e.g., inorganic semiconductors). For design approaches that embed stretchability in interconnect structures that join rigid device islands, the system level stretchability ε system is much smaller than the interconnect stretchability ε interconnect .…”

“…Structure designs for stretchable interconnects have evolved from straight [13,16] to curvilinear interconnects, [17] from those bonded to or embedded in the supporting substrate [11,18] to free-standing designs housed in microfluidic enclosures, [19] and from simple structures [17] to fractal/self-similar designs. [15,[20][21][22] All such cases, including a broad variety of shapes, sizes, and geometric arrangements, share the same underlying mechanisms, i.e., out-of-plane buckling of thin structures (metals, insulators, or semiconductors with thickness typically between ≈100 nm and ≈1 µm) provides the basis for elastic stretchability.…”

Three-dimensional nanonetworks for giant stretchability in dielectrics and conductors

“…Three-dimensional nanonetworks for giant stretchability in dielectrics and conductors Junyong Park 1 …”

Solderable and electroplatable flexible electronic circuit on a porous stretchable elastomer

“…A key technical issue is the development of tissue-like wearable or implantable electronics that are tissue-and skin-compatible, resistant to body fluids, flexible and sufficiently stretchable to adapt to tissue and body motions while maintaining close contact with the curvature of skin or organs. To date, several flexible or stretchable electronics for biomedical or industrial applications [3][4][5][6][7][8][9][10][11] have been developed. Metal thin-film deposition on a flexible substrate, such as polyimide (PI), has been a standard approach [12][13][14][15][16][17][18] , although the elasticity of PI is limited and thin metal patterns can tolerate only limited deformation before breaking.…”