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Application filed by Taiwan Semiconductor MfgfiledCriticalTaiwan Semiconductor Mfg
Priority to TW88113417ApriorityCriticalpatent/TW430989B/en
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Publication of TW430989BpublicationCriticalpatent/TW430989B/en
A method for forming the bit isolation layer of mask ROM is introduced. First, provide a semiconductor substrate and form an oxide layer on it. Define photoresist mask to cover the oxide layer to form the source/drain area of mask ROM. Proceed the first ion implantation and make buried N-type region in the source/drain area. Finally, proceed the second ion implantation process by using the photoresist mask as mask of ion implantation to dope conductive impurity into the semiconductor substrate and form the isolation area of a planar mask ROM in the part of the substrate under the buried N-type region.
TW88113417A1999-08-051999-08-05Bit isolation area formation of planar mask ROM
TW430989B
(en)