Test piece and manufacturing method thereof

A manufacturing method of a test piece, comprising:

• a first vacuum coating step for forming a first metal film on the insulating substrate by evaporation, sputtering, or atomic layer deposition (ALD);
• a second vacuum coating step for forming a second metal film on the first metal film by evaporation, sputtering, or ALD;
• a photolithography step for forming a photoresist pattern layer on the second metal film;
• a first etching step for removing parts of the second metal film which is uncovered by the photoresist pattern layer by using a first etchant to form a second metal pattern layer;
• a second etching step for removing parts of the first metal film which is uncovered by the photoresist pattern layer and the second metal pattern layer by using a second etchant to form a first metal pattern layer;
• a photoresist removing step for removing the photoresist pattern layer;
• and
• a chemical build-up step for forming a third metal pattern layer, a fourth metal pattern layer, and a fifth metal pattern layer on the second metal pattern layer in sequence by electroplating or electroless plating,
• wherein the first metal pattern layer, the second metal pattern layer, the third metal pattern layer, the fourth metal pattern layer, and the fifth metal pattern layer have same pattern shapes and positions thereof are overlapping in a plane, the first etchant is not reacting to the first metal film, and the second etchant is not reacting to the second metal pattern layer.