| 摘要 |
PURPOSE:To form buried layers for leading out electrodes easily by a method wherein a compound semiconductor substrate is etched through apertures formed in a dielectric film to form holes. CONSTITUTION:A collector layer, a base layer and an emitter layer 12-16 are formed on a GaAs substrate 11. After semi-insulating buried layers 17 are formed in the substrate 11, an SiO2 film is deposited on the substrate surface and apertures are made in the parts where P-type buried layers 18 for leading out base electrodes 21 are to formed. Then holes are drilled by etching through the apertures and the P-type buried layers 18 are formed in the holes. Then, likewise, N-type buried layers 19 are formed. After that, an emitter electrode 20, the base electrodes 21 and collector electrodes 22 are formed on the layer 16, the layers 18 and the layers 19 respectively. With this constitution, the buried layers for leading out electrodes can be formed easily and a transistor which has a flat top surface can be formed.
|
