| 摘要 |
PURPOSE:To reduce the chip area by etching other side of a semi-insulating chemical compound substrate along a metallic line formed on one side of the semi-insulating chemical compound semiconductor substrate so as to form a groove and to form a ground metal onto the entire face of the semi-insulated chemical compound substrate including the groove. CONSTITUTION:The metallic line 2 is formed to one side of the semi-insulating chemical semiconductor substrate 1, the other side of the semi-insulating chemical conductor substrate 1 is etched along the metallic line 2 to form the groove 3 and the ground metal 4 is formed to the entire face of the semi-insulating chemical conductor substrate 1 including the groove 3. Since the ground metal 5 is approached more than the ground metal 4 of the substrate 1 other than that under the metallic line 2, the metallic line 2 gives a lower impedance than the metallic line of the same width on the same substrate and the characteristic impedance of the transmission line is controlled by the etching quantity of the semi-insulating chemical compound semiconductor substrate 1 at the side of the ground metal 4. |
