Abstract: An image sensor is provided. The image sensor includes a pixel array, a sense amplifier, an analog-to-digital converter, a processor and a voltage generator. The sense amplifier obtains a first signal according to a pixel signal from the pixel array and a reference voltage, wherein the reference voltage has a first voltage level. The analog-to-digital converter converts the first signal into a first digital signal. The processor provides a feedback signal according to the first digital signal. The voltage generator adjusts the reference voltage to a second voltage level corresponding to the feedback signal. The sense amplifier removes a direct current (DC) bias voltage from the pixel signal according to the reference signal having the second voltage level.

Abstract: An improved APD structure and an improved manner of operating APD's particularly beneficial for a single photon detection applications are provided. An APD is provided having an absorption region, a control region, and a multiplication region, wherein the multiplication region has a k value of approximately 1. In one example the multiplication region comprises a doped InP layer. The field control layer is designed so as to produce a reduction of electric field that is equal to the multiplication region's breakdown electric field, plus or minus 5V/&mgr;m. The method comprises applying a potential across the APD so as to induce an electric field across the multiplication region that exceeds the breakdown field; while having the control region shield the absorption region to prevent excessive noise.

Abstract: A system for probe-less non-invasive detection of electrical signals from integrated circuit devices is disclosed. The system includes an illumination source, collection optics, imaging optics, and a photon sensor. In a navigation mode, the light source is activated and the imaging optics is used to identify the target area on the chip and appropriately position the collection optics. Once the collection optics is appropriately positioned, the light source is deactivated and the photon sensor is used to detect photons emitted from the chip. No mention of cooling (active device measurement capability) and advanced optics to detect the features (SIL).

Abstract: A bi-convex solid immersion lens is disclosed. Unlike conventional plano-convex solid immersion lenses having a flat bottom surface, the disclosed lens has a convex bottom surface. The radius of curvature of the bottom surface is smaller than that of the object to be inspected. This construction allows for a more accurate determination of the location of the inspected feature, and enhances coupling of light between the immersion lens and the inspected object. The disclosed lens is particularly useful for use in microscope for inspection of semiconductor devices and, especially flip-chip (or chip scale) packaged devices. The immersion lens can also be incorporated in a read or read/write head of optical memory media.