Abstract: A scanning electron microscope (SEM) includes an electron gun, a deflector, an objective lens, first and second detectors each configured to detect emission electrons emitted from the wafer based on the input electron beam being irradiated on the wafer, a first energy filter configured to block electrons having energy less than a first energy among emission electrons emitted from a wafer based on an input electron beam from being detected by the first detector, and a second energy filter configured to block electrons having energy less than second energy among the emission electrons from being detected by the second detector.

Abstract: A test apparatus includes a movable stage to support a sample, tips above the stage that have different shapes and alternately perform profiling and milling on the sample, a tip stage connected to a cantilever coupled to the tips, the tip stage to adjust a position of the cantilever, a position sensor to obtain information about a positional relationship between the tips and the sample, a stage controller to control movements of the stage and the tip stage, based on the information about the positional relationship, and a tip controller to select the tips for performing the profiling or milling and to determine conditions for performing milling, wherein a depth of the sample being processed by the milling in the first direction is controlled based on a relationship between a distance between the tips and the sample and a force between the tips and the sample.

Abstract: A test apparatus includes a movable stage to support a sample, tips above the stage that have different shapes and alternately perform profiling and milling on the sample, a tip stage connected to a cantilever coupled to the tips, the tip stage to adjust a position of the cantilever, a position sensor to obtain information about a positional relationship between the tips and the sample, a stage controller to control movements of the stage and the tip stage, based on the information about the positional relationship, and a tip controller to select the tips for performing the profiling or milling and to determine conditions for performing milling, wherein a depth of the sample being processed by the milling in the first direction is controlled based on a relationship between a distance between the tips and the sample and a force between the tips and the sample.

Abstract: An scanning electron microscope (SEM) image distortion correction method includes obtaining at least one SEM image of holes provided on a wafer in a two-dimensional array structure, the holes including at least one central hole within a central region of the at least one SEM image and a plurality of peripheral holes outside the central region, expanding each of the plurality of peripheral holes in a minor axis direction such that a ratio of a minor axis to a major axis of each of the plurality of peripheral holes is about 1:1, and expanding each of the plurality of peripheral holes in multiple directions in the at least one SEM image such that a diameter of the at least one central hole and a diameter of at least one of the plurality of peripheral holes are substantially equal to each other.

Abstract: A pattern inspection apparatus includes a sample including a plurality of holes having thicknesses that are different from each other, an electron gun configured to generate an input electron beam and emit the input electron beam onto a wafer and the sample, a stage configured to support the wafer and the sample, a detector configured to generate a scanning electron microscope (SEM) image by detecting emitted electrons from the wafer and the sample, and a processor configured to process the SEM image into a three-dimensional profiling image containing depth information of the wafer and determine whether a condition of the input electron beam has changed based on the processing of the SEM image.

Abstract: A method of operating an atomic force microscope (AFM) is provided. The method includes inspecting a sample by using the AFM and inspecting a tip of a probe of the AFM by using a characterization sample. The characterization sample includes a first characterization pattern that includes a line and space pattern of a first height, a second characterization pattern that includes a line and space pattern of a second height that is lower than the first height, and a third characterization pattern that includes a line and space pattern of a third height that is lower than the second height, and includes a rough surface.

Abstract: A scanning electron microscope (SEM) includes an electron gun, a deflector, an objective lens, first and second detectors each configured to detect emission electrons emitted from the wafer based on the input electron beam being irradiated on the wafer, a first energy filter configured to block electrons having energy less than a first energy among emission electrons emitted from a wafer based on an input electron beam from being detected by the first detector, and a second energy filter configured to block electrons having energy less than second energy among the emission electrons from being detected by the second detector.

Abstract: A test apparatus includes a movable stage to support a sample, tips above the stage that have different shapes and alternately perform profiling and milling on the sample, a tip stage connected to a cantilever coupled to the tips, the tip stage to adjust a position of the cantilever, a position sensor to obtain information about a positional relationship between the tips and the sample, a stage controller to control movements of the stage and the tip stage, based on the information about the positional relationship, and a tip controller to select the tips for performing the profiling or milling and to determine conditions for performing milling, wherein a depth of the sample being processed by the milling in the first direction is controlled based on a relationship between a distance between the tips and the sample and a force between the tips and the sample.

Abstract: According to embodiments, a wafer inspection device is provided. The wafer inspection device includes a porous chuck including a plurality of pores formed all over the porous chuck to allow pressure for fixing a wafer to be applied thereto, a chuck driving device, a back side inspection optical system configured to inspect a portion of a back surface of the wafer, and a position identification optical system, wherein the porous chuck includes a plurality of holes uniformly formed all over the porous chuck to partially expose the back surface of the wafer and a slit exposing the back surface of the wafer and extending in one direction parallel to a top surface of the porous chuck.

Abstract: According to embodiments, a wafer inspection device is provided. The wafer inspection device includes a porous chuck including a plurality of pores formed all over the porous chuck to allow pressure for fixing a wafer to be applied thereto, a chuck driving device, a back side inspection optical system configured to inspect a portion of a back surface of the wafer, and a position identification optical system, wherein the porous chuck includes a plurality of holes uniformly formed all over the porous chuck to partially expose the back surface of the wafer and a slit exposing the back surface of the wafer and extending in one direction parallel to a top surface of the porous chuck.

Abstract: Light-emitting devices having a multiple quantum well (MQW) diode structure and methods of making and using the devices are provided. The devices include aluminum nitride/aluminum oxide bilayers on their hole injection layers. The bilayers improve the energy efficiency of the devices, with respect to devices that lack the bilayers or that include only a layer of aluminum oxide on their hole injection layers.

Abstract: Disclosed herein is a data transmission apparatus including: a clock generating unit generating a clock signal by combining a first unit clock signal and a second unit clock signal formed by delaying the first unit clock signal by a predetermined time; a transmission controlling unit transmitting data in synchronization with the generated clock signal, thereby making it possible to transmit more data at a high speed.