Abstract: A method includes: forming overlay structures at scribe lines of a wafer, each side of a die region of the wafer is disposed with at least one of the overlay structures, each of the overlay structures comprises at least one feature and at least one recess disposed above the feature, the feature and the recess are respectively disposed at a first and second layers of the wafer, the recess exposes a portion of the feature vertically aligned with the recess; acquiring an image of the overlay structures; measuring a first dimension and a second dimension of a first portion and a second portion of the recess, respectively; determining an overlay between the first and second layers of an edge region of the wafer based on an average of differences between the first and second dimensions; and modifying a subsequent lithography step to compensate for the overlay.

Abstract: A method includes: forming overlay structures at scribe lines of a wafer, each side of a die region of the wafer is disposed with at least one of the overlay structures, each of the overlay structures comprises at least one feature and at least one recess disposed above the feature, the feature and the recess are respectively disposed at a first and second layers of the wafer, the recess exposes a portion of the feature vertically aligned with the recess; acquiring an image of the overlay structures; measuring a first dimension and a second dimension of a first portion and a second portion of the recess, respectively; determining an overlay between the first and second layers of an edge region of the wafer based on an average of differences between the first and second dimensions; and modifying a subsequent lithography step to compensate for the overlay.

Abstract: The present invention discloses a compact sensor package structure, which comprises a package body, an LED chip and a sensor chip. The package body has a first room, a second room, a first hole and a second hole. The first and second rooms are independent to each other. The first and second holes interconnect the interiors and the external environments of the first and second rooms. The LED chip is arranged inside the first room, corresponding to the first hole and below the first hole. The LED chip projects light through the first hole. The sensor chip is arranged inside the second room, corresponding to the second hole and above/below the second hole. The sensor chip receives light via the second hole. The present invention features two independent rooms for two chips and prevents interference between the two chips.

Abstract: A method and apparatus for detecting the added functions of a telephone dialer by adding diodes to the IC circuit and using as part of the input pins such that the need for total number of input pins and thus the manufacturing costs of the IC are reduced. The method is executed by using the available keyboard input/output boards without increasing the need for extra input pins in order to detect whether there is any diode in existence that is connected among the input/output ports.