Patent ID: 8293124
Filing Date: 2012-10-23
Classification: B44C,H01L,H03B

Abstract:
1. A method of multi-stage substrate etching, comprising the steps of: forming a first mask pattern on one surface of a first substrate; forming a hole by etching the first substrate using the first mask pattern as an etching mask; forming a second mask pattern on one surface of a second substrate; forming a hole by etching the second substrate to a depth using the second mask pattern as an etching mask; bonding the first and second substrates together such that an etched surface of the first substrate faces an etched surface of the second substrate; forming a third mask pattern on the second substrate, wherein the third mask pattern has a same pattern as the second mask pattern; forming a hole passing through the second substrate by etching the second substrate using the third mask pattern as an etching mask; and removing the third mask pattern to form a step structure.