| 摘要 |
PURPOSE:To obtain a memory which can be manufactured easily and constructed in a highly integrated manner and can hold data desirably by forming a vertical bipolar transistor to be utilized both for writing data in and for reading data from floating gates. CONSTITUTION:P-type floating gates 103, 103b are formed on a P-type semiconductor substrate 100 through an insulating film 102. Then, read bit lines 104 are provided by an N-type doped layer. Further, patterns of N-type word lines 105, 105b are provided and P-type write bit lines 106, 106b are provided thereon. According to such arrangement, when a voltage is applied to the word lines in a writing process, charges move between the write lines and the floating gates by bipolar operations. When a voltage is applied to the word lines in a reading process, data are obtained based on whether any charge is present in the floating gates or not. In this manner, the word lines can be used in common for both of writing and reading processes. Thus, it is possible to realize a memory which is constructed in a highly integrated manner and still can be manufactured easily. |
