A light absorption apparatus includes a substrate, a light absorption layer above the substrate on a first selected area, a silicon layer above the light absorption layer, a spacer surrounding at least part of the sidewall of the light absorption layer, an isolation layer surrounding at least part of the spacer, wherein the light absorption apparatus can achieve high bandwidth and low dark current.

A number of micro-sized rectangular dot-like n-type semiconductor regions 121 are created in a p-type semiconductor region which is a base body 11. Contact parts 14, each of which is in contact with one n-type semiconductor region 121 and almost entirely covers the same region, are mutually connected by a wire part 15 as a common cathode terminal. The n-type semiconductor regions 121 receives no light; their function is to collect carriers generated within and outside the surrounding depletion layers. Appropriate setting of the spacing of the n-type semiconductor regions 121 enables efficient collection of the carriers generated in the p-type semiconductor region while improving the SN ratio of the photo-detection signal by a noise-reduction effect due to a decrease in the p-n junction capacitance. Carriers originating from light of shorter wavelengths are barely reflected in the photo-detection signal. Thus, unfavorable influences of the shorter wavelengths of light are eliminated.

The present disclosure provides a semiconductor device and a semiconductor component. The semiconductor device includes an active structure, a ring-shaped semiconductor contact layer, a first electrode, and an insulating layer. The active structure has a first-conductivity-type semiconductor layer, a second-conductivity-type semiconductor layer, and an active layer located between the first-conductivity-type semiconductor layer and the second-conductivity-type semiconductor layer. The ring-shaped semiconductor contact layer is located on the second-conductivity-type semiconductor layer and having a first inner sidewall and a first outer sidewall. The first electrode has an upper surface and covers the ring-shaped semiconductor contact layer. The insulating layer covers the first electrode and the active structure and has a second inner sidewall and a second outer sidewall. The first inner sidewall is not flush with the second inner sidewall in a vertical direction.

In one embodiment, a photo detector is provided with a semiconductor layer having a projection portion provided at a side opposite to a light receiving surface side, and a reflective material which covers a surface of the projection portion and reflects a light incident from the light receiving surface. In the photo detector, the projection portion layer has a slope portion, and an angle α of a slope surface of the slope portion to the light receiving surface satisfies

[00001]$\frac{1}{2}.Math.\arcsin .Math.\frac{1}{n_1}\le \alpha \le \frac{1}{2}.Math.\arctan .Math.\frac{L}{D}$ using a refractive index n.sub.1 of the projection portion of the semiconductor layer, a length D of the semiconductor layer in a direction from the light receiving surface toward the projection portion, and a length L of the projection portion in the horizontal direction.

A photovoltaic photodetector includes a substrate, a graphene layer, and a dielectric layer positioned between the substrate and the graphene layer. One or more first antenna electrodes includes a first metal in direct contact with the graphene layer. One or more second antenna electrodes includes a second metal in direct contact with the graphene layer. The first and second metals have different work functions. A drain electrode is electrically coupled to the one or more first antenna electrodes, and a source electrode is electrically coupled to the one or more second antenna electrodes. The photovoltaic photodetector can be configured to be operable over a wavelength region of 2 μm to 24 μm and has a response time of 10 ns or less.

A Schottky diode is monolithically integrated into the core of an infrared semiconductor laser (e.g., a quantum cascade laser) to create a heterodyned infrared transceiver. The internal mode field of the infrared semiconductor laser couples to an embedded Schottky diode and can mix the infrared fields to generate a response at the difference frequency.

Disclosed is an active photonic device having a Darlington configuration with a substrate and a collector layer that is over the substrate. The collector layer includes an inner collector region. An outer collector region substantially surrounds the inner collector region and is spaced apart from the inner collector region. A base layer is over the collector layer. A first outer base region and a second outer base region substantially surround the inner base region and are spaced apart from the inner base region and each other. An emitter layer is over the base layer. The emitter layer includes an inner emitter region that is ring-shaped and resides over and extends substantially around an outer periphery of the inner base region. A first outer emitter region and a second outer emitter region substantially surround the inner emitter region and are spaced apart from the inner emitter region and each other.

Methods, systems, and devices are disclosed for low noise and high efficiency photoelectric amplification based on cycling excitation process (CEP). In some aspects, a device for amplifying signals of light-induced photocurrent includes an anode connected to a positive terminal of a voltage source; a disordered material layer coupled to the anode, wherein the disordered material layer is structured to have a thickness of 100 nm or less; and a cathode coupled to the disordered material layer and connected to a negative terminal of the voltage source, in which the device is operable to amplify photoexcited carriers based on photon absorption to produce an external quantum efficiency of the device that is at least 100%.

A contact to a semiconductor layer in a light emitting structure is provided. The contact can include a plurality of contact areas formed of a metal and separated by a set of voids. The contact areas can be separated from one another by a characteristic distance selected based on a set of attributes of a semiconductor contact structure of the contact and a characteristic contact length scale of the contact. The voids can be configured to increase an overall reflectivity or transparency of the contact.

An ultraviolet (UV) photo-detecting device, including: a substrate; a first nitride layer disposed on the substrate; a second nitride layer disposed between the first nitride layer and the substrate; a light absorption layer disposed on the first nitride layer; and a Schottky junction layer disposed on the light absorption layer.