| 摘要 |
PURPOSE:To suppress the evaporation of the substrate constituents and obtain an insulating film with excellent interface while forming an insulating film by means of CVD method, by adding phospher pressure to be obtained by the thermal degradation of organic phospher compounds until just before the formation of the film or during the film formation. CONSTITUTION:The InP substrate 3 is subjected to resistive heating in the atmosphere of N2 gas from the tube 16, and until the temperature reaches at a fixed stable point between 200-400 deg.C N2 gas containing vapor of (CH3O)3P are sent in at the rate of 100cc/min. After the system of the reactive furnace 15 is stabilized, the feed of organic phospher compounds from the tube 6 is stopped and immediately N2 gas containing vapor of Al (COC3H7)37 is sent in at the rate of 3,500cc/min to form Al2O3 film. With such as arrangement, as P obtained from the thermal degradation of (CH2O)3P prevents the evaporation of P from the InP substrate and protect the surface of the substrate until just before the formation of Al2O3 film, the properties of the device never deteriorate. Also the employment of P pressure obtained from the thermal degradation of (CH3O)3P to all the film formation process by CVD method is likewise effective. |
