Method of cleaning semiconductor wafer and method of manufacturing semiconductor wafer

A method of cleaning a semiconductor wafer, the method comprising:

• a first step of measuring a contact angle of a surface of a semiconductor wafer using a droplet dripped on the surface of the semiconductor wafer under a plurality of conditions in which a volume of the droplet dripped on the surface differs;
• a second step of, based on a relationship between measured values of the volume of the droplet and measured values of the contact angle under the plurality of conditions, calculating a ratio of change in the measured values of the contact angle to change in the measured values of the volume of the droplet;
• a third step of determining whether pretreatment is necessary for the surface of the semiconductor wafer based on the ratio;
• a fourth step of performing the pretreatment on the surface of the semiconductor wafer according to the determining in the third step;
• and
• a fifth step of subsequently performing single-wafer spin cleaning on the surface of the semiconductor wafer.