Wafers used for evaluating semiconductor manufacturing equipment, materials, and electrical properties, also known as dummy wafers. Depending on the evaluation, a variety of test wafers such as bare wafers, blanket film-coated wafers, and patterned wafers are used selectively.

Wafers that have undergone deposition processing of semiconductor films, insulating films, metal films, etc., on the substrate, without any further processing. These are also referred to as coated wafers, deposition wafers, or blanket wafers.

In semiconductor manufacturing processes that use plasma or charged particles, the charge from the plasma or charged particles redistributes, penetrating the gate oxide film of the MOS structure to form an electric field.

A patterned wafer that has undergone trench (groove) shaping. It is used for evaluations such as step coverage assessment of deposition equipment.