OPTICAL MODULATOR OF ULTRA-HIGH SPEED SEMICONDUCTOR AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A method for manufacturing an optical modulator of an ultra-high speed semiconductor is to provide a superior modulation characteristic, by simultaneously reducing contact resistance and capacitance which are a cause decreasing a characteristic of the optical modulator. CONSTITUTION: An n-type optical waveguide layer(22), an optical absorbing layer(23), a p-type optical waveguide layer(24), a p-type clad layer(25) and a p-type ohmic contact layer(26) are sequentially formed on a substrate(21) to make a ridge structure. The p-type ohmic contact layer is etched to have a width of W1. The n-type optical waveguide layer, the optical absorbing layer, the p-type optical waveguide layer, the p-type clad layer and the p-type ohmic contact layer are vertically etched to have a width of W2. The optical absorbing layer is laterally etched to have a width of W3 narrower than W1.