Abstract
The previous report, Part 1, described the merits of alkaline electrolytic etching combined with acid chemical etching for Ge-In alloyed junction element. However, this technique needed a lot of processes in after-etching. On the other hand, acid chemical etching deteriorated the mechanical structure of P-N-P alloyed junction element for high frequency use. But, the above demerits could be eliminated by mixing of water, hydrogen peroxide, and hydrofluoric acid in proper ratios. The technique of acid chemical etching is used for the production of high frequency transistor. The results of experiments showed high inversed voltages, VCBO and VEBO, and stability of other electric characteristics.The specifications of the etchants for experiments were as follows.Etchant group Composition (in vol. ratio)154 etchant H2O:H2O2:HF 1:5:4253 etchant H2O:H2O2:HF 2:5:4433 etchant H2O:H2O2:HF 4:3:3By the improved acid etching with 154 etchant (in etching for 40s), the best results were obtained in electric characteristics and mass production.
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call