A STUDY OF THE MECHANISM OF REACTIVE STRIPPING OF PHOTORESIST

Reactive strippers are now widely used in semiconductor manufacture fo r the removal of photoresists. This paper describes the use of track d evelopment monitoring and a Fabry-Perot interferometric method to quan titatively assess the removal of hardbaked and plasma-treated photores ist from silicon substrates. The Fabry-Perot interferometric system al lows visualization of the processes which occur when the strippers are placed in contact with resist. It is evident that these strippers do not simply dissolve the photoresist but promote removal through the ge neration of crazing and disruption of the resist polymer by the produc tion of minute bubbles at the silicon oxide-resist interface or within the bulk resist.