Charged particle beam apparatus

A charged particle beam apparatus comprising:

• a charged particle source generating a charged particle beam with which a sample is irradiated;
• a light source generating a light with which the sample is irradiated;
• a first detector detecting secondary charged particles obtained by irradiating the sample with the charged particle beam;
• a stage on which the sample is mounted;
• a position adjustment sample mounted on the stage and irradiated with the charged particle beam and the light;
• a second detector detecting a secondary light obtained by irradiating the position adjustment sample with the light;
• a computer system controlling irradiation with the charged particle beam and irradiation with the light, acquiring a first detection signal by the first detector and a second detection signal by the second detector, and generating and displaying an image;
• and
• a mechanism setting an irradiation position of the charged particle beam and an irradiation position of the light with respect to the stage and changing a relative positional relationship including a distance between the irradiation position of the light and the stage, under control of the computer system,
• wherein the position adjustment sample has a structure where an insulating film as a first area and a conductive plug and an impurity diffusion layer under the insulating film as a second area are periodically arranged on a surface of a silicon wafer and, due to irradiation with a light having a wavelength that activates a junction formed with the silicon wafer and the impurity diffusion layer as the light, charging on the surface is removed or reduced to increase the number of secondary charged particles emitted, and
• wherein the computer system:
• generates an image in which an irradiation area of the light is reflected as an intensity distribution based on the first detection signal obtained by irradiating the position adjustment sample with both the charged particle beam and the light;
• and
• adjusts the irradiation position of the charged particle beam and the irradiation position of the light based on the image obtained when the positional relationship is changed by the mechanism.

A charged particle beam apparatus comprising:

• a charged particle source generating a charged particle beam with which a sample is irradiated;
• a light source generating a light with which the sample is irradiated;
• a first detector detecting secondary charged particles obtained by irradiating the sample with the charged particle beam;
• a stage on which the sample is mounted;
• a position adjustment mark provided on the stage and irradiated with the charged particle beam and the light;
• a position adjustment sample mounted on the stage and irradiated with the charged particle beam and the light;
• a second detector detecting a secondary light obtained by irradiating the position adjustment mark or the position adjustment sample with the light;
• a computer system controlling irradiation with the charged particle beam and irradiation with the light, acquiring a first detection signal by the first detector and a second detection signal by the second detector, and generating and displaying an image;
• and
• a mechanism setting an irradiation position of the charged particle beam and an irradiation position of the light with respect to the stage and changing a relative positional relationship including a distance between the irradiation position of the light and the stage, under control of the computer system,
• wherein the position adjustment sample has a structure where an insulating film as a first area and a conductive plug and an impurity diffusion layer under the insulating film as a second area are periodically arranged on a surface of a silicon wafer and, due to irradiation with a light having a wavelength that activates a junction formed with the silicon wafer and the impurity diffusion layer as the light, charging on the surface is removed or reduced to increase the number of secondary charged particles emitted, and
• wherein the computer system:
• as first adjustment,
• generates a first image in which the position adjustment mark is reflected based on the first detection signal obtained by irradiating the position adjustment mark with the charged particle beam;
• generates a second image in which an irradiation area of the light is reflected in the vicinity of the position adjustment mark based on the second detection signal obtained by irradiating the position adjustment mark with the light;
• adjusts the irradiation position of the charged particle beam and the irradiation position of the light based on the first image and the second image obtained when the positional relationship is changed by the mechanism;
• as second adjustment,
• generates an image in which an irradiation area of the light is reflected as an intensity distribution based on the first detection signal obtained by irradiating the position adjustment sample with both the charged particle beam and the light;
• and
• adjusts the irradiation position of the charged particle beam and the irradiation position of the light based on the image obtained when the positional relationship is changed by the mechanism.

A charged particle beam apparatus comprising:

• a charged particle source generating a charged particle beam with which a sample is irradiated;
• a light source generating a light with which the sample is irradiated;
• a detector detecting secondary charged particles obtained by irradiating the sample with the charged particle beam;
• a stage on which the sample is mounted;
• a position adjustment mark provided on the stage and irradiated with the charged particle beam and the light;
• a computer system controlling irradiation with the charged particle beam and the irradiation with the light, acquiring a detection signal by the detector, and generating and displaying the image;
• a mechanism setting an irradiation position of the charged particle beam and an irradiation position of the light with respect to the stage and changing a relative positional relationship including a distance between the irradiation position of the light and the stage, under control of the computer system,
• wherein the detector detects photoelectrons obtained by irradiating the position adjustment mark with the light, and
• wherein the computer system:
• generates a first image in which the position adjustment mark is reflected based on the detection signal obtained by irradiating the position adjustment mark with the charged particle beam;
• generates a second image in which an irradiation area of the light is reflected in the vicinity of the position adjustment mark based on the detection signal obtained by irradiating the position adjustment mark with the light;
• and
• adjusts the irradiation position of the charged particle beam and the irradiation position of the light based on the first image and the second image obtained when the positional relationship is changed by the mechanism.