Means and method for improved junction isolation

摘要: @ An improved means and method for forming junction isolated device regions is described wherein there provided a semiconductor substrate (50) in which has been etched tub (52) corresponding to the desired location depth of device. In preferred embodiment, filled with three successive epitaxial layers. The first layer (53), opposite conductivity type more lightly doped than substrate, conformally coats bottom (52a) sidewalls (52b) (52). A second (54), generally solid solubility limit, formed within (53). This serves as buried collector region provides surface accessible contact collector. third (55) fills acts region. Higher breakdown voltages, lower isolation capacitance, economical manufacturing process result.