Solid-state laser system, phase matching method, and electronic device manufacturing method

A phase matching method for a wavelength conversion system including a first non-linear crystal that generates first wavelength-converted light based on a first laser beam and a second non-linear crystal that generates second wavelength-converted light based on the first wavelength-converted light output from the first non-linear crystal and a second laser beam, the phase matching method comprising:

• detecting at least one of the first wavelength-converted light and the first laser beam having passed through the second non-linear crystal;
• performing phase matching of the first wavelength-converted light in the first non-linear crystal based on at least one of intensity of the first wavelength-converted light and intensity of the first laser beam thus detected;
• detecting at least one of the second wavelength-converted light output from the second non-linear crystal, and the first wavelength-converted light and the second laser beam having passed through the second non-linear crystal after having performed adjustment in which the phase matching of the first wavelength-converted light is performed in the first non-linear crystal;
• and
• performing phase matching of the second wavelength-converted light in the second non-linear crystal based on at least one of intensity of the second wavelength-converted light, intensity of the first wavelength-converted light and intensity of the second laser beam thus detected, wherein:
• the phase matching of the first wavelength-converted light includes adjusting a first incident angle of light on the first non-linear crystal to maximize the intensity of the first wavelength-converted light or minimize the intensity of the first laser beam;
• and
• the phase matching of the second wavelength-converted light includes adjusting a second incident angle of light on the second non-linear crystal to maximize the intensity of the second wavelength-converted light or minimize one of the intensity of the first wavelength-converted light and the intensity of the second laser beam.

An electronic device manufacturing method comprising:

• generating a third laser beam by using a solid-state laser system, the solid-state laser system including
• a first laser apparatus configured to output a first laser beam,
• a second laser apparatus configured to output a second laser beam,
• a first non-linear crystal that generates first wavelength-converted light based on the first laser beam,
• a first adjustment unit configured to perform phase matching of the first wavelength-converted light in the first non-linear crystal, the first adjustment unit including a first angle adjustment mechanism configured to change a first incident angle of light on the first non-linear crystal,
• a second non-linear crystal that is disposed on an optical path of the first wavelength-converted light and generates second wavelength-converted light based on the first wavelength-converted light and the second laser beam,
• a second adjustment unit configured to perform phase matching of the second wavelength-converted light in the second non-linear crystal, the second adjustment unit including a second angle adjustment mechanism configured to change a second incident angle of light on the second non-linear crystal,
• a wavelength selection element disposed on an optical path of light output from the second non-linear crystal,
• a light detection unit configured to detect light having a wavelength selected by passing through the wavelength selection element, and
• a processor configured to:
• control the first adjustment unit based on at least one of intensity of the first wavelength-converted light having passed through the second non-linear crystal and detected by the light detection unit and intensity of the first laser beam having passed through the second non-linear crystal and detected by the light detection unit;
• perform the phase matching of the first wavelength-converted light by controlling the first angle adjustment mechanism to adjust the first incident angle to maximize the intensity of the first wavelength-converted light or minimize the intensity of the first laser beam;
• control the second adjustment unit based on at least one of intensity of the second wavelength-converted light detected by the light detection unit, the intensity of the first wavelength-converted light having passed through the second non-linear crystal and detected by the light detection unit and intensity of the second laser beam having passed through the second non-linear crystal and detected by the light detection unit;
• and
• perform the phase matching of the second wavelength-converted light by controlling the second angle adjustment mechanism to adjust the second incident angle to maximize the intensity of the second wavelength-converted light or minimize one of the intensity of the first wavelength-converted light and the intensity of the second laser beam;
• outputting the third laser beam to an exposure apparatus;
• and
• exposing a photosensitive substrate to the third laser beam in the exposure apparatus to manufacture an electronic device.