| 摘要 |
PURPOSE:To shorten a distance between groove-shaped capacitors remarkably by forming a first conduction type impurity diffusion region having junction depth shallower than a second conduction type impurity diffusion region shaped in an impurity diffusion region in the inner surface of a groove section formed while reaching in a semiconductor layer from the surface of a well region. CONSTITUTION:A P type well region 22 is buried selectively to the surface layer of a semiconductor substrate 21. A groove-shaped capacitor 25a has a groove section 26a shaped while reaching into the substrate 21 from the surface of the region 22. A P type diffusion region 27a is formed to the region 22 in the inner surface of the groove section 26a and the substrate 21. An N type diffusion region 28a shallower than the region 27a is formed in the region 27a. An electrode 30 is shaped extending over the periphery of an opening section for the groove section 26a through an insulating film 31a for the capacitor. The electrode 30 and the region 28a function as first and second capacitor electrodes. Accordingly, a distance between groove-shaped capacitors is shortened remarkably without generating a punch-through phenomenon, and the density of a memory cell can be increased. |
