| 摘要 |
PURPOSE: A test pattern is provided to evaluate accurately the plasma charging damage from metal etching process. CONSTITUTION: A test pattern comprises: a first metal pad(23) which is formed in a matrix form, having a plurality of via contacts(21) and metal bars(22) acting as a metal antenna; a second metal pad(24) formed as wrapping the first metal pad; a MOSFET(26) which is constructed on the outer part of the second metal pad and of which gate is connected to the first metal pad; and a protection diode(27) connected to the second metal pad through the via contact. The plasma charging damage generated in a first metal etch process do damage to a gate(25) through the first metal pad. Thus, the test pattern can measure the plasma charging damage, and the first metal pad(23) and a probe chip can form a contact which has very small resistance because the probe tip is thick compared with the distance between metal bars(22) when the probe tip is connected to the first metal pad(23). In addition, the first pad is connected to a second metal pad(24) including a protection diode(27), and when doing this, the accumulated effect of plasma charging damage by both the first etching process and IMD(Inter Metal Direction) processing is estimated.
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