| 摘要 |
PURPOSE:To obtain a complementary insulated gate field effect transistor integrated circuit in which the elements are highly integrated by selecting the material or the film thickness of the gate insulation film, thereby setting the electrostatic capacity of the gate portion depending on the elements. CONSTITUTION:A diffusion region 24 constitutes the drain of a transistor Q1 and is connected to an electrode 26 by means of a contact hole 34. A transistor Q2 includes two diffusion regions 20 and 38 which are formed in a P-type well 36 formed on one main surface of a substrate 30, and on the main surface therebetween a gate electrode 14 composed of a polycrystalline silicon layer is formed. The gate lengths of the transistors Q1 and Q2 are both L and are effectively equal. The gate width Wp of the transistor Q1 and that Wn of the transistor Q2 are set effectively equal. For instance, if the gate insulation film thickness d1 of the transistor Q1 is 1,200 angstrom and that d2 of the transistor Q2 is 300 angstrom, the ratio betaR of the gain factor beta2 of the transistor Q2 to that beta1 of the transistor Q1 is set to 4. As apparent from this example, a desired betaR can be obtained by changing the gate insulation film thickness according to the elements, and thus degree of freedom is increased in the selection of the width and length of the gate electrode. |
