An InGaN/GaN multiple quantum well blue light detector- includes: a Si substrate, an AlN/AlGaN/GaN buffer layer, a u-GaN/AlN/u-GaN/SiN.sub.x/u-GaN buffer layer, an n-GaN buffer layer, an InGaN/GaN superlattice layer and an InGaN/GaN multiple quantum well layer in sequence from bottom to top. The multiple quantum well layer has a groove and a mesa, the mesa and the groove of the multiple quantum well layer are provided with a Si.sub.3N.sub.4 passivation layer. The passivation layer in the groove is provided with a first metal layer electrode with a semicircular cross section, and the passivation layer on the mesa is provided with second metal layer electrode.

An InGaN/GaN multiple quantum well blue light detector- includes: a Si substrate, an AlN/AlGaN/GaN buffer layer, a u-GaN/AlN/u-GaN/SiN.sub.x/u-GaN buffer layer, an n-GaN buffer layer, an InGaN/GaN superlattice layer and an InGaN/GaN multiple quantum well layer in sequence from bottom to top. The multiple quantum well layer has a groove and a mesa, the mesa and the groove of the multiple quantum well layer are provided with a Si.sub.3N.sub.4 passivation layer. The passivation layer in the groove is provided with a first metal layer electrode with a semicircular cross section, and the passivation layer on the mesa is provided with second metal layer electrode.

A photodetector includes an insulating layer on a substrate, a first graphene layer on the insulating layer, a 2-dimensional (2D) material layer on the first graphene layer, a second graphene layer on the 2D material layer, a first electrode on the first graphene layer, and a second electrode on the second graphene layer. The 2D material layer includes a barrier layer and a light absorption layer. The barrier layer has a larger bandgap than the light absorption layer.

The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.

The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.

The invention provides hybrid photovoltaic-piezoelectric energy harvesting devices in the form of flexible filaments. The devices harvest energy from ambient light, and also from environmental motions and vibrations. They are particularly suitable for incorporation into fabrics and clothing.

A multilayer stack including a substrate, an active layer, and a tetradymite buffer layer positioned between the substrate and the active layer is disclosed. A method for fabricating a multilayer stack including a substrate, a tetradymite buffer layer and an active layer is also disclosed. Use of such stacks may be in photovoltaics, solar cells, light emitting diodes, and night vision arrays, among other applications.

A vertical tunneling FET (TFET) provides low-power, high-speed switching performance for transistors having critical dimensions below 7 nm. The vertical TFET uses a gate-all-around (GAA) device architecture having a cylindrical structure that extends above the surface of a doped well formed in a silicon substrate. The cylindrical structure includes a lower drain region, a channel, and an upper source region, which are grown epitaxially from the doped well. The channel is made of intrinsic silicon, while the source and drain regions are doped in-situ. An annular gate surrounds the channel, capacitively controlling current flow through the channel from all sides. The source is electrically accessible via a front side contact, while the drain is accessed via a backside contact that provides low contact resistance and also serves as a heat sink. Reliability of vertical TFET integrated circuits is enhanced by coupling the vertical TFETs to electrostatic discharge (ESD) diodes.

A photovoltaic cell is provided that enables cost reduction and stable operation with a simple configuration and enhances conversion efficiency by a new technology of forming an energy level in a band gap. In the photovoltaic cell, a substrate, a conductive first electrode, an electromotive force layer, a p-type semiconductor layer, and a conductive second electrode are laminated, electromotive force is generated by photoexciting the electron in the band gap of the electromotive force layer by light irradiation, the electromotive force layer is filled with an n-type metal oxide semiconductor of fine particles coated by an insulating coat, a new energy level is formed in a band gap by photoexcited structural change caused by ultraviolet irradiation, and efficient and stable operation can be performed by providing a layer of an n-type metal oxide semiconductor between the first electrode and the electromotive force layer.

The present invention provides stretchable, and optionally printable, semiconductors and electronic circuits capable of providing good performance when stretched, compressed, flexed or otherwise deformed. Stretchable semiconductors and electronic circuits of the present invention preferred for some applications are flexible, in addition to being stretchable, and thus are capable of significant elongation, flexing, bending or other deformation along one or more axes. Further, stretchable semiconductors and electronic circuits of the present invention may be adapted to a wide range of device configurations to provide fully flexible electronic and optoelectronic devices.