| 摘要 |
<p>PURPOSE:To prevent a fault due to incident alpha-ray into a semiconductor device having an active region of an infinitesimal cell on its upper surface by brazing the bottom surface of the device onto a ceramic substrate having no recess and coating the active region by material containing no radioactive substance. CONSTITUTION:A first metallized film 3 is formed on the upper central surface of a ceramic substrate 1 having a flat surface formed thereon, and second and third metallized films 4a, 4b extended to both side surfaces of the substrate 1 are coated to surround the film 3. Then, a dynamic RAM cell 9 having a thickness of approx. 0.3mm and an active region 10 is brazed onto the central film 3, and electrodes provided at the cell 9 are connected respectively to the films 4a, 4b using wires 11a and 11b, respectively. A cup-like ceramic cover 13 is then coated over the cell 9, and a silicon shield 14 having a thickness of more than 0.3mm, separated by 0.65mm from the cell 9 and extended by approx. 2.0mm at its outside from the region 10 in the cover 13. Thus, alpha-ray from the cover 13 and the substrate 1 cannot be incident to the region 10.</p> |
