Semiconductor memory device

Abstract

Abstract PURPOSE:To eliminate the leakage of charges to a substrate and a malfunction resulting from alpha-rays, to enable correct operation by increasing the quantity of charges stored and to lengthen a memory holding time by forming three layers constituting a capacitor cell. CONSTITUTION:A groove 2 is dug to a P type semiconductor substrate 1, and a P<+> diffusion layer 10 is shaped onto the inner surface of the groove. An insulating layer 4 consisting of SiO2 on the inside of the diffusion layer 10 and a polysilicon layer 11 on the inside of the layer 4 are formed. An insulating layer 4 on the inside of the layer 11 and a polysilicon layer 12 on the inside of the layer 4 are shaped. An N channel MOS transistor 6 for taking in and out charges to and from the capacitor cell is formed. According to the constitution, a capacitor element is connected in parallel, thus doubling the quantity of charges stored. Charges are stored in the layer 11 through the transistor 6, thus resulting in no leakage to the substrate 1, then preventing the effect of electrons generated in the substrate 1 by alpha-rays.

Inventors

• 👤 Yukimasa Uchida
• 👤 内田　幸正
• 👤 Toru Kimura
• 👤 亨 木村

Bibliographic Details