Embodiments relate to systems and methods for sensor self-diagnostics using multiple signal paths. In an embodiment, the sensors are magnetic field sensors, and the systems and/or methods are configured to meet or exceed relevant safety or other industry standards, such as SIL standards. For example, a monolithic integrated circuit sensor system implemented on a single semiconductor ship can include a first sensor device having a first signal path for a first sensor signal on a semiconductor chip; and a second sensor device having a second signal path for a second sensor signal on the semiconductor chip, the second signal path distinct from the first signal path, wherein a comparison of the first signal path signal and the second signal path signal provides a sensor system self-test.

A method of conducting an in situ reliability test on a cross-section of a device with layered structure at micron-scale and at least two electrodes. The method includes steps of locating an electron transparent cross-sectional portion of the device in a holder and transmitting a direct current bias voltage to the cross-sectional portion of the device through at least two electrodes of the device, and observing and quantifying the microstructural changes of the device cross-section on the holder. A system for conducting an in situ reliability test on a device with a layered structure at a micron-scale and at least two electrodes is also provided.

A semiconductor device may include a substrate, active circuitry on the substrate and including differential transistor pairs, and threshold voltage test circuitry on the substrate. The threshold voltage test circuitry may include a pair of differential test transistors replicating the differential transistor pairs within the active circuitry, with each test transistor having a respective input and output, and at least one gain stage configured to amplify a difference between the outputs of the differential test transistors for measuring a threshold voltage thereof. The differential transistor pairs and the pair of differential test transistors may each include spaced apart source and drain regions, a channel region extending between the source and drain regions, and a gate overlying the channel region. Each of the channel regions may include a superlattice.

A testkey structure including the following components is provided. A fin structure is disposed on a substrate and stretches along a first direction. A first gate structure and a second gate structure are disposed on the fin structure and stretch along a second direction. A first common source region is disposed in the fin structure between the first gate structure and the second gate structure. A first drain region is disposed in the fin structure at a side of the first gate structure opposite to the first common source region. A second drain region disposed in the fin structure at a side of the second gate structure opposite to the first common source region. A testkey structure is symmetrical along a horizontal line crossing the first common source region. The present invention further provides a method of measuring device defect or connection defect by using the same.

A semiconductor device includes a semiconductor layer having a first area and an edge termination area outside the first area. The semiconductor layer has a first conductivity type, an active area in the first area, a test area in the first area adjacent the active area, a first anode contact on the semiconductor layer in the active area, a second anode contact on the semiconductor layer in the test area, and a cathode contact in electrical contact with the semiconductor layer. A related method of testing surge current capability of a semiconductor device includes applying a forward current that is smaller than a maximum forward current of the semiconductor device to a test active area that is within an area inside a main edge termination area of the semiconductor device, and detecting a failure of the semiconductor device in response to the forward current.

A switch circuit connects an external inspection device to a first internal circuit, a second internal circuit, or both the first internal circuit and the second internal circuit in a state where the external inspection device is connected to an external terminal. A switch control circuit selects a connection destination of the external inspection device in the switch circuit based on a test setting signal from outside.

A semiconductor substrate in includes a buffer layer and a first crystalline layer. A bandgap of the first crystalline layer is smaller than a bandgap of a second layer. When a semiconductor wafer is formed as a transistor wafer, a channel of a transistor is formed at or near an interface between the first crystalline layer and the second layer. With a first electrode and a second electrode provided and a third electrode provided, when space charge redistribution, for emitting electrons and holes from a bandgap of a crystal positioned in the spatial region, is achieved by applying negative voltage to the third electrode or by applying positive voltage to the second electrode with the first electrode serving as a reference, an electron emission speed in the space charge redistribution is higher than a hole emission speed.

Disclosed is a non-invasive online monitoring circuit for an on-state saturation voltage of a power semiconductor, including one or more basic units; each basic unit includes a normally-ON switching device, a diode, and a clamping voltage supply; a gate of the normally-ON switching device is connected to a positive electrode of the clamping voltage supply; the positive electrode of the diode is connected to a source of the normally-ON switching device, and a negative electrode of the diode is connected to the gate of the normally-ON switching device; the drain of the normally-ON switching device and the negative electrode of the clamping voltage supply serve as input terminals of the monitoring circuit for accessing the power semiconductor under test; and the source of the normally-ON switching device and the negative electrode of the clamping voltage supply serve as output terminals of the monitoring circuit.

The present disclosure provides test structures, fabrication methods thereof and test methods thereof. An exemplary test structure includes a substrate having a to-be-tested region having at least one fin and a peripheral region having at least one fin surrounding the to-be-tested region; an insulation layer covering portions of side surfaces of the fins; at least one first gate structure covering side and top surfaces of the fin in the to-be-tested region; second gate structures covering side and top surfaces of the fins in the peripheral region; source/drain regions formed in portions of the fins between adjacent second gate structures and portions of the fins between the first gate structure and adjacent second gate structures; and a plurality of first conductive structures formed between adjacent second gate structures in the peripheral region. The plurality of first conductive structures cross over and are on source/drain regions of at least two fins.

A nitride semiconductor epitaxial stack structure including: a Silicon substrate; an aluminum-including nucleation layer disposed on the silicon substrate; a buffer structure disposed on the aluminum-including nucleation layer and sequentially including: a first superlattice epitaxial structure, a first GaN based thick layer disposed on the first superlattice epitaxial structure, a second superlattice epitaxial structure disposed on the first GaN based thick layer, and a second GaN based thick layer disposed on the second superlattice epitaxial structure; a channel layer disposed on the buffer structure; a barrier layer disposed on the channel layer; and a two dimensional electron gas layer disposed near an interface between the channel layer and the barrier layer, wherein the total thickness of the first GaN based thick layer and the second GaN based thick layer is more than 2 micrometers.