| 摘要 |
<p>PURPOSE:To arrange comb-shaped P-type and N-type impurity regions in such a way that their comb-teeth mesh with each other and to obtain a photo diode having a horizontal type P-N junction by a method wherein a single-layer semiconductor substrate thin film is formed through an insulating layer on a semiconductor substrate and the comb-shaped P-type and N-type impurity regions to oppose to this thin film are formed. CONSTITUTION:An insulating layer 2 consisting of an Si oxide film is formed on a semiconductor substrate 1 by performing a thermal oxidation. A single- layer poly Si layer is deposited on this layer 2 by an LPCVD method and phosphorus P ions are implanted in this whole poly Si layer to turn the whole layer into an N<-> impurity region. Then, a patterning of the poly Si layer is performed to form a poly Si layer 3 of a configuration necessary for a thin film PSD. A thin Si oxide film is formed on this layer 3 by performing a thermal oxidation and phosphorus P ions are implanted in the layer 3 using a photoresist as a mask to form a comb-shaped N<-> impurity region 5. Similarly, a P-type impurity region 7b, a comb-shaped P<+> impurity region 7a adjacent to the region 7b, P<+> impurity regions 9a and 9b and so on are formed by an ion-implantation of boron B.</p> |
