Politecnico Di Milano

Google Inc.

Agilent Technologies, Inc.

Daimler Chrysler Ag

Lorenzo Colace

Gianlorenzo Masini

Giovanni Isella

Andrea Ballabio

Jacopo Frigerio

Andrea De Iacovo

Hartmut Presting

Gaetano Assanto

Thomas Pearsall

A double photodiode electromagnetic radiation sensor device including a substrate, a first integrated photodiode (PD), a second integrated photodiode (PD), and more than one metal contact. The substrate may be within a first semiconductor material that defines a first face and a second face. The PDmay include a first doped region extending to the second face and a 'n-' type doping. The PDmay further include a second doped region extending to the second face having a “p+” type doping. The PDmay include the first doped region, and a layer in a second semiconductor material placed on the second face in contact with the first doped region defining a third face. The PDmay yet further include a doped layer in the second semiconductor material having a “p+” type doping and overlapping the third face.

Double photodiode electromagnetic radiation sensor device

An electromagnetic radiation spectrum detection system including a sensor device and an electronic control and processing module. The sensor device may include two photodiodes. The sensor device may convert an incident electromagnetic radiation (EMR) into electrical current. The electronic control and processing module may store numerical calibration values representative of a responsivity matrix of the sensor device. The electronic control and processing module may selectively provide the sensor device with electrical control voltage values (V). The electronic control and processing module may process the values of detected electric currents (Iph) and the numerical calibration values to obtain spectrum information related to incident electromagnetic radiation spectrums. The electronic control and processing module may determine power spectral density of incident electromagnetic radiation.

Electromagnetic radiation spectrum detection system

A photodetector structure includes a silicon-based waveguide in which optical signals to be detected travel in a given direction and are confined therein and a germanium layer disposed in contact with a portion of the silicon-based waveguide so that an evanescent tail of the propagating optical signal in the waveguide is coupled into the germanium layer. In addition, the germanium layer includes a mesa having a length along the signal propagating direction and a width in a direction substantially perpendicular to the propagating direction, in which the width of said mesa is smaller than its length. The photodetector also comprises a first and a second metal contacts, the first metallic contact being located on the germanium layer, the said second metallic contact being located on the silicon-based waveguide, the first and second contacts being used to collect electrons generated by light absorption to obtain an output electric signal.

Photodetector in germanium on silicon

A device for stabilizing the operating wavelength (&lgr;) of an electro-optical component having a nominal operating wavelength (&lgr; ) by a wavelength influencing circuit adapted to be driven by a control signal. The device comprises a semiconductor photodiode adapted to be impinged upon by the radiation generated and/or processed by the component and to generate an output signal which is indicative of a difference of the wavelength of the radiation ((&lgr;) with respect to the nominal operating wavelength (&lgr; , &lgr; ). The semiconductor photodiode includes a plurality of layers jointly defining two opposite diodes generating opposite photocurrents as a result of radiation impinging onto the photodiode. The opposite photocurrents are adapted to generate the control signal to effect the stabilization action.

Wavelength sensitive device for wavelength stabilization

A voltage-controlled, wavelenght-selective photodetector includes comprising a double diode having a counter-polarized Si-Schottky diode and a SiGe PIN diode. The short-wave portion (&lgr;<0.9 &mgr;m) of the light entering the detector through a window generates electron-hole pairs in the Si-Schottky diode, while the longer-wave portion (1 &mgr;m<&lgr;<2 &mgr;m) passes through the substrate and is absorbed in the epitaxially deposited SiGe superlattice or the quantum well diode. The photocurrents of both detectors flow in physically opposite directions and subtract from each other, resulting in a wavelength-dependent operational sign of the photocurrent. The level of the bias voltage applied determines whether the photocurrent of the Si-Schottky diode or the photocurrent of the Si/Ge PIN diode determines the spectrum. This can be used, for example, in an application for decoding signals by transforming the light signal into an electrical output signal and subtracting the photocurrents of the two detectors which filters out the noise component and thus raises the signal/noise ratio of a light signal.

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Rome, Italy

Lorenzo Colace