Method for manufacturing semiconductor device
Abstract
Abstract A method for manufacturing a semiconductor device comprises the steps of forming a trench (2) on the major surface of a semiconductor substrate (1) and depositing a polysilicon film (5) on the entire surface of the semiconductor substrate (1) including the inside of said trench (2). In order to form complete isolation in the bottom portion of the trench (2), the trench (2) is filled with an oxide film (10). A refractory metal (12) such as tungsten which can be selectively deposited on polysilicon is deposited only on the polysilicon film (5) on the major surface of the semiconductor substrate (1). The oxide (10) inside the trench (2) removed and then, anisotropic etching of the polysilicon film (5) in the bottom portion of the trench (2) is performed utilizing the refractory metal (12) as a mask, so that isolation is formed in a self-aligning manner. thereafter, an oxide film (13) and a polysilicon film (14) are formed successively, so that three-dimensional charge storage capacitance is achieved.
Inventors
- 👤 Yoshinori Okumura
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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| 7.5 Years (Year 8) | 1995-05-03 | 1995-11-02 | 1996-05-03 | $3760.00 | Window Closed / Lapsed |
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