| 摘要 |
PURPOSE:To apply the trench etching technology to the planar cell structure for enhancing the integration thereof. CONSTITUTION:Trenches 4 in parallel with one another are formed on a silicon substrate 2 while N type high concentration impurity diffused layers 6 to be sources are formed on the bottom parts of the trenches 4 while the other high concentration impurity diffused layers 8 to be bit lines (draina) are formed on the rest parts of the protrusions on the substrate 2 held by the adjacent trenches 4. At this time, P type high concentration diffused layers 11 are formed on the bases of the protrusions to separate the gaps between the adjacent sources 6 and 6 for increasing the breakdown strength. On the other hand, gate oxide films 10 are formed on the sides of the trenches 4. In such a constitution, word lines, 14 comprising polycide layers are orthogonal to the direction of the trenches 4 while the parts wherein the word lines 14 intersect with the sides of the trenches 4 are to be the channel regions. |
