TW256944B - IC buried contact process - Google Patents

Abstract

An IC buried contact process includes: (1) forming oxide on one Si substrate to define active area; (2) in sequence forming one gate oxide, one first conductive layer, and one masking layer covering the Si substrate; (3) forming one U-form trench in the masking layer, the first conductive layer, and the gate oxide layer, which is located on the active area edge and extended to on the field oxide layer; (4) forming one second conductive layer filling up the U-form trench in order to forming one U-form contact plug; (5) etching the specified area of masking layer, the first conductive layer, and the second conductive layer to form gate electrode and contact interconnection, in which the gate electrode is cross the active area enter, and the contact interconnection crosses over the field oxide and connects to other active area with the U-form contact plug as starting point; (6) ion implanting with the gate electrode and the contact interconnection as mask, forming heavily doped source/drain electrode area on the Si substrate; (7) forming one pre-metal dielectric layer, completing the buried contact process.