1. Field of the Invention
This invention relates to a sample processing apparatus for inspecting the surface of a sample, and more particularly to a sample processing apparatus and method by which it is inspected whether or not there is a foreign matter sticking to the surface of a sample such as a semiconductor wafer or a glass substrate.
2. Description of the Related Art
Conventionally, in a process of production of a semiconductor device, it must be inspected whether or not there is a foreign matter sticking to the surface of a semiconductor wafer determined as a circuit board, and variable surface inspection apparatus are available which realize such inspection.
A surface inspection apparatus of the type mentioned generally irradiates a laser beam onto the surface of a sample while the sample is moved so that the surface thereof is optically scanned to detect a foreign matter. If a foreign matter is detected on the surface of the sample by the optical scanning, then the position of the foreign matter on the surface of the sample is recorded as data.
The sample from which the foreign matter is detected in this manner is moved, when necessary, from the surface inspection apparatus to a separate foreign matter analyzer, by which the composition of the foreign matter is analyzed based on the position data.
In the analysis of the composition by the foreign matter analyzer, for example, the sample is placed into the inside of a vacuum vessel which is then evacuated. Then, a charged particle beam such as an electron beam or an ion beam is irradiated at the position of the foreign matter of the sample, and a secondary electron beam and/or a reflected electron beam and secondary ions generated as a result of the irradiation are detected.
If a result of the analysis reveals that the foreign matter will be an obstacle to operation of an electronic circuit, then the sample is moved from the foreign matter analyzer to a separate foreign matter removal apparatus, by which the foreign matter is removed based on the position data.
Such removal of the foreign matter by the foreign matter removal apparatus is performed, for example, by irradiating a laser beam to evaporate the foreign matter.
Since a fine foreign matter sticking to the surface of a sample can be detected and removed if a surface inspection apparatus, a foreign matter analyzer and a foreign matter removal apparatus are used as described above, this can contribute to production of, for example, an electronic circuit which will not suffer from an obstacle to its operation thereof.
However, such successive movements of a sample to different apparatus as described above complicate the operation and lowers the productivity of electronic circuits.
Further, installation of such various apparatus as mentioned above disadvantageously increases the area occupying by the equipment.
Furthermore, when a foreign matter is processed by the foreign matter analyzer or the foreign matter removal apparatus based on position data detected by the surface inspection apparatus as described above, since the sample is moved between the different apparatus, there is the possibility that the position data and the actual position of the foreign matter may be displaced from each other.