| 摘要 |
PURPOSE: To form a large area of multicolor light emitting elements by forming light emitting layers different in the degree of porosity in the regions where a plurality of first electrodes provided in the specified direction on an insulating substrate and a plurality of second electrodes cross each other at right angles. CONSTITUTION: A transparent conductive film of indium oxide ITO where tin is added is made about 2000Å thick all over the surface as a first electrode 2 on a glass substrate 1 by high frequency sputtering. A polycrystalline silicon layer or an amorphous silicon layer is made 2-30μm thick in the specified section of the top of the glass board 1, and it is doped with boron as impurities to form a p-type layer 3. Next, an anode is made, with the first electrode 2 as an anode, and the surface of the layer 3 is made porous to make a porous silicon layer 4. Next, a stripe-shaped second electrode 5 is made by etching it after sputtering Al or ITO all over the surface. Porous silicon at the intersecting point is made to emit light by applying DC to the electrode selected out of the first and second electrodes 2 and 5. Hereby, a multicolor large screen can be obtained. |
