Abstract: The invention relates to a device (10,20) for detecting a phase difference between two light beams (8A, 8B), said device including: a diffraction grating (2) which can generate an interference field between the two light beams; and a photodiode (1,5) which is arranged to receive the interference field, said diffraction grating being integrated to the photodiode. The invention is characterized in that the diffraction grating is an amplitude grating (2).

Abstract: The method of and apparatus for testing a floating gate non-volatile memory semiconductor device comprising an array of cells including floating gates for storing data in the form of electrical charge. The method includes applying a test pattern of said electrical charge to the floating gates, exposing the device to energy to accelerate leakage of the electrical charges out of the cells, and subsequently comparing the remaining electrical charges in the cells to the test pattern. The energy is applied in the form of electromagnetic radiation of a wavelength such as to excite the charges in the floating gates to an energy level sufficient for accelerating charge loss from the floating gates of defective cells relative to charge loss from non-defective cells. The wavelength is preferably in the range of 440 to 560 nm.

Abstract: The invention relates to a device (10, 20) for detecting a phase difference between two light beams (8A, 8B), said device including: a diffraction grating (2) which can generate an interference field between the two light beams; and a photodiode (1,5) which is arranged to receive the interference field, said diffraction grating being integrated into the photodiode. The invention is characterized in that the diffraction grating is an amplitude grating (2).

Abstract: A method of and apparatus for testing a floating gate non-volatile memory semiconductor device comprising an array of cells including floating gates for storing data in the form of electrical charge. The method includes applying a test pattern of said electrical charge to the floating gates, exposing the device to energy to accelerate leakage of the electrical charges out of the cells, and subsequently comparing the remaining electrical charges in the cells to the test pattern. The energy is applied in the form of electromagnetic radiation of a wavelength such as to excite the charges in the floating gates to an energy level sufficient for accelerating charge loss from the floating gates of defective cells relative to charge loss from non-defective cells. The wavelength is preferably in the range of 440 to 560 nm.

Abstract: An amplifying device for a sensor (10) delivering a response in voltage or impedance has a voltage controlling means for the sensor and at least an additional impedance (12). The voltage controlling means (22) is connected to output terminals (16, 20) of the sensor to maintain a noticeably constant voltage between the terminals. The additional impedance (12) is connected in series with the sensor within a polarization circuit, between the output terminals (18–16; 18–20) of the device. The amplifying device may be applied to temperatures, irradiation levels and pH measurement.

Abstract: A semiconductor device comprising superimposed layers of p- and n-doped semiconducting material (e.g. silicon) and electrical contact means for applying an electrical potential across the superimposed layers is characterized in that the p- and n-doped layers are both of amorphous semiconducting mateial (e.g. silicon) and one of said layers is much more heavily doped than the other. Suitably the less heavily doped layer has a thickness which is not greater than 2 .mu.m and the dopant concentration in the more heavily doped layer is one hundred or more times the dopant concentration of the less heavily doped layer. Preferably a third or quasi-intrinsic layer or substantially undoped amorphous semiconducting material (e.g. silicon) or electrically insulating material is applied to one of the doped layers between that layer and its electrical contact means. The device can be used as an electrically-programmable non-volatile semiconductor memory device.