| 摘要 |
PURPOSE:To simplify a manufacture process and to reduce cost on the whole by forming an n<+> layer and an electrode 4 in order on a glass substrate or plastic substrate coated with an amorphous silicon layer. CONSTITUTION:Then n<+> layer 3 and electrode 4 are formed in order on the glass substrate 1 or plastic substrate 1 coated with the amorphous silicon layer 2, and they are further coated with an amorphous silicon layer 2 to form an ISFET. The silicon layer 2 is used as a pH sensing layer and a hydroxy group is present in the surface of this amorphous silicon nitride, so surface charges vary with the hydrogen ion concentration in a solution and the interface potential also varies at the same time, so that the variation is measured by using a measuring instrument. Further, the substrate is constituted by using an inexpensive and nonbrittle glass plate or plastic sheet and an amorphous film is formed thereupon by using a plasma CVD device. Thus, the manufacture is facilitated and the cost is reduced. |
