Abstract: Two pairs of alignment targets (one aligned, one misaligned by a bias distance) are formed on different masks to produce a first pair of conjugated interference patterns. Other pairs of alignment targets are also formed on the masks to produce a second pair of conjugated interference patterns that are inverted the first. Misalignment of the dark and light regions of first interference patterns and the second interference patterns in both pairs of conjugated interference patterns is determined when patterns formed using the masks are overlaid. A magnification factor (of the interference pattern misalignment to the target misalignment) is calculated as a ratio of the difference of misalignment of the relatively dark and relatively light regions in the pairs of interference patterns, over twice the bias distance. The interference pattern misalignment is divided by the magnification factor to produce a self-referenced and self-calibrated target misalignment amount, which is then output.

Abstract: Two pairs of alignment targets (one aligned, one misaligned by a bias distance) are formed on different masks to produce a first pair of conjugated interference patterns. Other pairs of alignment targets are also formed on the masks to produce a second pair of conjugated interference patterns that are inverted the first. Misalignment of the dark and light regions of first interference patterns and the second interference patterns in both pairs of conjugated interference patterns is determined when patterns formed using the masks are overlaid. A magnification factor (of the interference pattern misalignment to the target misalignment) is calculated as a ratio of the difference of misalignment of the relatively dark and relatively light regions in the pairs of interference patterns, over twice the bias distance. The interference pattern misalignment is divided by the magnification factor to produce a self-referenced and self-calibrated target misalignment amount, which is then output.

Abstract: Two pairs of alignment targets (one aligned, one misaligned by a bias distance) are formed on different masks to produce a first pair of conjugated interference patterns. Other pairs of alignment targets are also formed on the masks to produce a second pair of conjugated interference patterns that are inverted the first. Misalignment of the dark and light regions of the first interference patterns and the second interference patterns in both pairs of conjugated interference patterns is determined when patterns formed using the masks are overlaid. A magnification factor (of the interference pattern misalignment to the target misalignment) is calculated as a ratio of the difference of misalignment of the relatively dark and relatively light regions in the pairs of interference patterns, over twice the bias distance. The interference pattern misalignment is divided by the magnification factor to produce a self-referenced and self-calibrated target misalignment amount, which is then output.

Abstract: In an exemplary method, a first layer is formed on a substrate. First overlay marks are formed in a first zone of the first layer. A non-transparent layer is formed on top of the first layer. At least a portion of the non-transparent layer is removed from an area above the first zone of the first layer. This provides optical access to the first overlay marks. A second layer is formed on top of the non-transparent layer. Second overlay marks are formed in a second zone of the second layer. Position information is obtained from each of the first overlay marks and the second overlay marks.

Abstract: Two pairs of alignment targets (one aligned, one misaligned by a bias distance) are formed on different masks to produce a first pair of conjugated interference patterns. Other pairs of alignment targets are also formed on the masks to produce a second pair of conjugated interference patterns that are inverted the first. Misalignment of the dark and light regions of the first interference patterns and the second interference patterns in both pairs of conjugated interference patterns is determined when patterns formed using the masks are overlaid. A magnification factor (of the interference pattern misalignment to the target misalignment) is calculated as a ratio of the difference of misalignment of the relatively dark and relatively light regions in the pairs of interference patterns, over twice the bias distance. The interference pattern misalignment is divided by the magnification factor to produce a self-referenced and self-calibrated target misalignment amount, which is then output.

Abstract: Two pairs of alignment targets (one aligned, one misaligned by a bias distance) are formed on different masks to produce a first pair of conjugated interference patterns. Other pairs of alignment targets are also formed on the masks to produce a second pair of conjugated interference patterns that are inverted the first. Misalignment of the dark and light regions of the first interference patterns and the second interference patterns in both pairs of conjugated interference patterns is determined when patterns formed using the masks are overlaid. A magnification factor (of the interference pattern misalignment to the target misalignment) is calculated as a ratio of the difference of misalignment of the relatively dark and relatively light regions in the pairs of interference patterns, over twice the bias distance. The interference pattern misalignment is divided by the magnification factor to produce a self-referenced and self-calibrated target misalignment amount, which is then output.

Abstract: In an exemplary method, a first layer is formed on a substrate. First overlay marks are formed in a first zone of the first layer. A non-transparent layer is formed on top of the first layer. At least a portion of the non-transparent layer is removed from an area above the first zone of the first layer. This provides optical access to the first overlay marks. A second layer is formed on top of the non-transparent layer. Second overlay marks are formed in a second zone of the second layer. Position information is obtained from each of the first overlay marks and the second overlay marks.

Abstract: In an exemplary method, a first layer is formed on a substrate. First overlay marks are formed in a first zone of the first layer. A non-transparent layer is formed on top of the first layer. At least a portion of the non-transparent layer is removed from an area above the first zone of the first layer. This provides optical access to the first overlay marks. A second layer is formed on top of the non-transparent layer. Second overlay marks are formed in a second zone of the second layer. Position information is obtained from each of the first overlay marks and the second overlay marks.

Abstract: In an exemplary method, a first layer is formed on a substrate. First overlay marks are formed in a first zone of the first layer. A non-transparent layer is formed on top of the first layer. At least a portion of the non-transparent layer is removed from an area above the first zone of the first layer. This provides optical access to the first overlay marks. A second layer is formed on top of the non-transparent layer. Second overlay marks are formed in a second zone of the second layer. Position information is obtained from each of the first overlay marks and the second overlay marks.

Abstract: Two pairs of alignment targets (one aligned, one misaligned by a bias distance) are formed on different masks to produce a first pair of conjugated interference patterns. Other pairs of alignment targets are also formed on the masks to produce a second pair of conjugated interference patterns that are inverted the first. Misalignment of the dark and light regions of the first interference patterns and the second interference patterns in both pairs of conjugated interference patterns is determined when patterns formed using the masks are overlaid. A magnification factor (of the interference pattern misalignment to the target misalignment) is calculated as a ratio of the difference of misalignment of the relatively dark and relatively light regions in the pairs of interference patterns, over twice the bias distance. The interference pattern misalignment is divided by the magnification factor to produce a self-referenced and self-calibrated target misalignment amount, which is then output.

Abstract: Language learning and speech training techniques are implemented to provide automated and real-time quantitative feedback to the user. Sound samples produced by a speaker are transcribed and analyzed against database sound samples to: provide speech therapy, compute the accuracy of a speaker's pronunciation, aid in learning a foreign language, and help members of the deaf community learn to communicate with spoken language.