A non-volatile memory in which a leak current from an electric charge accumulating layer to an active layer is reduced and a method of manufacturing the non-volatile memory are provided. In a non-volatile memory made from a semiconductor thin film that is formed on a substrate (101) having an insulating surface, active layer side ends (110) are tapered. This makes the thickness of a first insulating film (106), which is formed by a thermal oxidization process, at the active layer side ends (110) the same as the thickness of the rest of the first insulating film. Therefore local thinning of the first insulating film does not take place. Moreover, the tapered active layer side ends hardly tolerate electric field concentration at active layer side end corners (111). Accordingly, a leak current from an electric charge accumulating layer (107) to the active layer (105) is reduced to improve the electric charge holding characteristic. As a result, the first insulating film can be further made thin to obtain a high performance non-volatile memory that operates at a low voltage and consumes less power.