Method of manufacturing an epitaxial wafer comprising measuring a level difference between a front surface of a susceptor and an upper surface of a lift pin and adjusting a ratio of the heat source output

A method of manufacturing an epitaxial wafer, the method including growing an epitaxial layer on a substrate placed on a susceptor while heating the substrate with upper and lower heat sources located above and beneath the susceptor, respectively, in a state where an upper surface of a lift pin inserted in a through-hole having openings at a front and a rear surfaces of the susceptor has a level difference with respect to the opening at the front surface side,

• the method including an adjustment step of measuring a level difference from the opening to the upper surface of the lift pin in the above state, and adjusting a ratio of the output of the upper heat source located above the susceptor to the output of the lower heat source located beneath the susceptor on the basis of the measured level difference,
• an appropriate pair of the level difference and the ratio of the outputs, which pair is suitable for flattening a surface of the epitaxial layer, has been set in advance within a predetermined range of the level difference in the state where the upper surface of the lift pin retracts in the through-hole,
• in the adjustment step, when the measured level difference is within the predetermined range, the outputs of the heaters are adjusted to the ratio that makes an appropriate pair with the measured level difference, and
• the appropriate pair of the level difference and the ratio of the outputs has been set as follows:
• the greater the retraction amount of the upper surface of the lift pin with respect to the opening is, the greater the ratio of the output of the lower heat source to the sum of the output of the upper and the lower heat source is.