Light modulator module and method for fabricating light modulator module

摘要

A light modulator module includes a submount; a semiconductor laser and a semiconductor light modulator having a signal input terminal integrated on the submount, the semiconductor laser outputting laser light and the semiconductor light modulator modulating the laser light in response to a high-frequency signal input to the signal input terminal; a strip line for transmitting the high-frequency signal, the strip line having first and second terminals, the second terminal receiving the high-frequency signal; a terminating resistor terminating the strip line and having opposed first and second ends with the second end being grounded; a first wire connecting the signal input terminal of the semiconductor light modulator to the first terminal of the strip line; and a second wire connecting the first end of the terminating resistor to the signal input terminal of the semiconductor light modulator. In this structure, the inductances of the first and second wires are present between the signal supply and the terminating resistor. When the frequency of the signal is increased, current flowing in the terminating resistor decreases, compensating for an increase in current flowing through the light modulator, whereby the frequency dependence of the total current is reduced. Deviation of impedance from a prescribed value and return loss are reduced.