Abstract: A memory element having a large memory window and a high reliability is provided at low cost by performing high speed write and erase operations at a relatively low voltage and suppressing rewrite degradation. A memory element includes a semiconductor layer arranged on an insulating substrate, a first diffusion layer region and a second diffusion layer region having a conductivity type of P-type, a charge accumulating film for covering a channel region between the first diffusion layer region and the second diffusion layer region and being injected with charges from the channel region, and a gate electrode positioned on a side opposite to the channel region with the charge accumulating film in between.

Abstract: A chain-like toy made of a plurality of isosceles triangular hollow prism units that are connected serially with one another at slanted side planes thereof by means of a connecting rod interposed with a resilient member, each unit being connected rotatably for an angle of 360.degree. so that various shapes of things can be simulated by rotating each of the triangular hollow prisms.