INTERFEROMETER FOR TSV MEASUREMENT AND MEASUREMENT METHOD USING SAME

摘要

The present invention relates to an interferometer for TSV measurement and a measurement method using the same, and according to the present invention, an interferometer for TSV measurement comprises: a beam splitter on which the light generated from a light source is incident and is divided and outputted in a first direction and a second direction that are vertical to each other, and which combines lights inputted from said first direction and said second direction and outputs a combined light; a measuring object having mirrors and at least one TSV, wherein the mirrors are respectively disposed in said first direction or said second direction and reflect, to said beam splitter, the outputted light which is outputted from said beam splitter after the light has been inputted; an imaging means which receives the combined light that is reflected from said mirrors and said measuring object and is outputted from said beam splitter, and forms an interference signal through said combined light; an object lens which is positioned between said beam splitter and said imaging means, or is positioned between said beam splitter and said measuring object; and a variable field stop which is positioned between said beam splitter and said imaging means, so that the focus of the lights divided on said measuring object can be adjusted to a reference position, which is the entrance of said TSV, and to a variable position, which is the bottom surface of said TSV, thereby measuring a diameter and a depth of a via hole on the basis of an interference signal at said reference position and the interference signal at said variable position. Thus, the invention provides the interferometer for TSV measurement and the measurement method using the same, in which: the diameter and the depth of the TSV are measured by using the variable field stop for adjusting the focus of the lights to the entrance and the bottom surface of the TSV during TSV measurement, thereby reducing measurement time and a capacity of result data; and a telecentric lens, which enables the light incident on the TSV to substantially become a straight light, is used such that the intensity of radiation can reach the bottom surface even though an aspect ratio like TSV is large, whereby the measurement accuracy is improved.