| 摘要 |
PURPOSE:To provide a forming method of a P-N junction capacitance wherein a sufficiently large junction capacitance can be obtained when the area of a P-N junction part is made small, regarding the forming method of a P-N junction capacitance and a semiconductor storage device. CONSTITUTION:After a first buried layer 3 of the opposite conductivity type is formed on a part of a semiconductor substrate 1 of a conductivity type, a first epitaxial layer 2 of the opposite conductivity type is formed. A second epitaxial layer 6 of the opposite conductivity type is formed by forming a second buried layer 7 of the opposite conductivity type so as to come into contact with the first buried layer 3. An impurity diffusion layer 9 of a conductivity type is formed by introducing impurities of a conductivity type into the region corresponding with the second buried layer 7 of the second epitaxial layer 6 and annealing the substrate. A P-N junction capacitance is formed between the impurity diffusion layer 9 of a conductivity type and the second buried layer 7 of the opposite conductivity type. |
