| 摘要 |
PURPOSE:To obtain the titled device of high integration degree whose floating gate can be properly controlled by a control gate by a method wherein the floating gate are overlapped with the control gate in a groove part provided at part of a field region. CONSTITUTION:The groove part 104 is formed by selectively etching a field oxide film 102 and further the surface region of an Si substrate 101 by using a resist pattern 103 as a mask. Next, after removal of the resist 103, oxide films 105 and 106 are grown on the surface of the substrate 101 of island form and on the inner surface of the groove 104, respectively, by thermal oxidation. Then, a polycrystalline Si film doped with an impurity is deposited and then patterned, resulting in the formation of the control gate 107 with one end side buried in the groove 104 via oxide film 106. After deposition of the polycrystalline Si film doped with an impurity, the floating gate 109 crossing the region of the substrate 101 of island form and laminated over the control gate 107 in the one end side groove 104 via oxide film 108 is formed by patterning. |
