| 摘要 |
PURPOSE:To obtain a microscopic electrostatic induction type FET in high reproducibility by forming the second insulating film around the first insulating film on a main surface of a semiconductor substrate, removing the second insulating film at a predetermined portion and introducing impurity thereinto. CONSTITUTION:The first insulating film 23 is formed on the epitaxial layer 22 of a semiconductor substrate 21. Oepnings 23a, 23b are perforated thereat, and alcohol solution of organic oxysilane is coated therethrough. The thin film 24 on the insulating film 23 is etched, and a thick insulating film 24 is retained within the openings. A resist mask 25 is coated thereon, the film 24a is etched, and the mask is then removed. The film 23 is not almost removed owing to the etching speed difference between the films 23 and 24, and the opening 24a is substantially retained. Then, impurity injection layer 26 is formed, the film 26b is removed, organic oxysilane is coated again thereon, is treated similarly to the previous treatment to form an impurity layer 29 thereon, and electrodes are selectively mounted to complete it. In this configuration, the opening distance of the layers 26 and 29 is made independent of the relative positioning accuracy to thus form a microscopic device in high reproducibility. |
