Abstract: In an optical carrier injection method, a pulsed optical beam having pulse duration of 900 fs or lower is applied on a backside of a substrate of an integrated circuit (IC) wafer or chip, and is focused at a focal point in an active layer on a frontside of the substrate. Photons of the optical beam are absorbed at the focal point by nonlinear optical interaction(s) to inject carriers. The pulsed optical beam may be applied using a fiber laser in which the fiber is doped with Yb and/or Er. An output signal may be measured, comprising an electrical signal or a light output signal produced by the IC wafer or chip in response to the injected carriers. By repeating the applying, focusing, and measuring over a grid of focal points in the active layer, an image of the IC wafer or chip may be generated.

Abstract: A multispectral inspection (MSI) device for analyzing an electronic item having a printed circuit board (PCB). An electronic power supply powers the electronic item in accordance with one or more test vectors. An optical imaging scanner, terahertz (THz) imaging scanner, and a functional imaging scanner are each operative to scan the electronic item. An electronic processor is programmed to scan the various scanners and control the power supply to acquire optical, THz, and functional images of the electronic item. The images are combined to form a standard three-dimensional (3D) signature and artificial intelligence (AI) classifiers are applied to the 3D signature to perform non-destructive analyses of the electronic item.

Abstract: A multispectral inspection (MSI) device for analyzing an electronic item having a printed circuit board (PCB). An electronic power supply powers the electronic item in accordance with one or more test vectors. An optical imaging scanner, terahertz (THz) imaging scanner, and a functional imaging scanner are each operative to scan the electronic item. An electronic processor is programmed to scan the various scanners and control the power supply to acquire optical, THz, and functional images of the electronic item. The images are combined to form a standard three-dimensional (3D) signature and artificial intelligence (AI) classifiers are applied to the 3D signature to perform non-destructive analyses of the electronic item.

Abstract: In an optical carrier injection method, a pulsed optical beam having pulse duration of 900 fs or lower is applied on a backside of a substrate of an integrated circuit (IC) wafer or chip, and is focused at a focal point in an active layer on a frontside of the substrate. Photons of the optical beam are absorbed at the focal point by nonlinear optical interaction(s) to inject carriers. The pulsed optical beam may be applied using a fiber laser in which the fiber is doped with Yb and/or Er. An output signal may be measured, comprising an electrical signal or a light output signal produced by the IC wafer or chip in response to the injected carriers. By repeating the applying, focusing, and measuring over a grid of focal points in the active layer, an image of the IC wafer or chip may be generated.

Abstract: To validate an integrated circuit (IC), the IC is imaged by scanning an optical beam over the IC to optically inject carriers and measuring an output signal generated by the IC in response to the injected optical carriers. A comparison between the image of the IC and a reference image is computed, and suspect regions of the IC are identified based on the comparison. The reference image may be an image of a reference IC. In another approach, images of training ICs are acquired, and a deep learning algorithm is trained to transform corresponding training IC layouts to the images of the training ICs. The trained deep learning algorithm then transforms a layout of the IC to generate the reference image. The comparison may be computed by computing an error metric for each region corresponding to a standard cell in the reference image.

Abstract: In an imaging method, a focal point of a focused optical beam is sequentially mechanically positioned at coarse locations in or on an integrated circuit (IC) wafer or chip. At each coarse location, a two-dimensional (2D) image or mapping tile is acquired by steering the focal point to fine locations on or in the IC wafer or chip using electronic beam steering and, with the focal point positioned at each fine location, acquiring an output signal produced in response to an electrical charge that is optically injected into the IC wafer or chip at the fine location by the focused optical beam. The 2D image or mapping tiles are combined, including stitching together overlapping 2D image or mapping tiles, to generate an image or mapping of the IC wafer or chip. The electronic beam steering may be performed using a galvo mirror. The set of coarse locations may span a three-dimensional (3D) volume.

Abstract: In an optical carrier injection method, a pulsed optical beam having pulse duration of 900 fs or lower is applied on a backside of a substrate of an integrated circuit (IC) wafer or chip, and is focused at a focal point in an active layer on a frontside of the substrate. Photons of the optical beam are absorbed at the focal point by nonlinear optical interaction(s) to inject carriers. The pulsed optical beam may be applied using a fiber laser in which the fiber is doped with Yb and/or Er. An output signal may be measured, comprising an electrical signal or a light output signal produced by the IC wafer or chip in response to the injected carriers. By repeating the applying, focusing, and measuring over a grid of focal points in the active layer, an image of the IC wafer or chip may be generated.

Abstract: A multispectral inspection (MSI) device for analyzing an electronic item having a printed circuit board (PCB). An electronic power supply powers the electronic item in accordance with one or more test vectors. An optical imaging scanner, terahertz (THz) imaging scanner, and a functional imaging scanner are each operative to scan the electronic item. An electronic processor is programmed to scan the various scanners and control the power supply to acquire optical, THz, and functional images of the electronic item. The images are combined to form a standard three-dimensional (3D) signature and artificial intelligence (AI) classifiers are applied to the 3D signature to perform non-destructive analyses of the electronic item.

Abstract: A diode comprises nanowires compositionally graded along their lengths with an active region doped with gadolinium sandwiched between first and second compositionally graded AlxGa1-xN nanowire regions. The first graded AlxGa1-xN nanowire region is graded from gallium-rich to aluminum-rich with the compositional grading defining n-type polarization doping and the aluminum-rich end proximate the active region. The second graded AlxGa1-xN nanowire region is graded from aluminum-rich to gallium-rich with the compositional grading defining p-type polarization doping and with the aluminum rich end proximate the active region. The active region may include a GdN layer sandwiched between AlN layers, or an Al1-yGdyN layer with y?0.5.

Abstract: A diode comprises nanowires compositionally graded along their lengths with an active region doped with gadolinium sandwiched between first and second compositionally graded AlxGa1-xN nanowire regions. The first graded AlxGa1-xN nanowire region is graded from gallium-rich to aluminum-rich with the compositional grading defining n-type polarization doping and the aluminum-rich end proximate the active region. The second graded AlxGa1-xN nanowire region is graded from aluminum-rich to gallium-rich with the compositional grading defining p-type polarization doping and with the aluminum rich end proximate the active region. The active region may include a GdN layer sandwiched between AlN layers, or an Al1-yGdyN layer with y?0.5.