Manufacture of semiconductor device
Abstract
Abstract PURPOSE: To form flat surface by covering a Si substrate surface and concave part flank with a Si 3 N 4 this film and by coverting all Si 3 N 4 into SiO 2 through oxidization. CONSTITUTION: The Si substrate 11 is etched by CF 4 gas via SiO 2 12 of 1μm to form concave part 13 of approximate 4500Å. After film 2 is removed, Si 3 N 4 14 of less than 300Å is formed and film 14 is removed by resist mask 15. Next, mask 15 is removed and a treatment is carried out at 1100°C for 150 minutes to produce separate oxidized film 16 of approximate 1μm in thickness. Since the flank of the concave part is covered with Si 3 N 4 14', no over-head occurs. In addition, films 14 and 14' are converted gradually into oxdized film to a thickness of approximate 700Å during a treatment, so that a completely-flat Si substrate surface can be obtained. COPYRIGHT: (C)1979,JPO&Japio
Inventors
- 👤 Tatsunori Nakajima
- 👤 Kosei Kajiwara
- 👤 Kazutoshi Nagano
Bibliographic Details
Claims Analysis
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