High-Speed Optical Transceiver
An optical transceiver includes a pad formed on the surface of a DSP package substrate. an optical modulation module, a package that accommodates the optical modulation module, and a pad formed on the surface of the package, and the DSP package substrate and the package are directly connected to each other by the pad and the pad.
1 . A high-speed optical transceiver comprising:
a digital signal processing circuit;
a first electrode formed on a first package substrate of the digital signal processing circuit;
an optical element;
a second package that accommodates the optical element; and
a second electrode formed on a surface of the second package,
wherein the first package substrate and the second package are directly connected to each other by the first electrode and the second electrode.
2 . The high-speed optical transceiver according to claim 1 , wherein the optical element includes at least one of an optical modulating element and a light receiving element.
3 . The high-speed optical transceiver according to claim 1 , wherein, in the first electrode and the second electrode, a width of a signal pad functioning as a signal line is 200 μm or less, a width of a signal pad of the second package is smaller than a width of a signal pad of the first package substrate, and a through hole for heating is formed.
4 . The high-speed optical transceiver according to claim 1 , wherein a solder resist is provided on at least one of the first electrode and the second electrode, and the first electrode and the second electrode are connected using a low melting point solder having a melting point of 150° C. or less.
5 . The high-speed optical transceiver according to claim 1 , wherein the second package is a ceramic package, and a total thickness of a region of the second package where the second electrode is formed is 1 mm or less.
6 . The high-speed optical transceiver according to claim 1 , wherein a height of a second formation surface on which the second electrode is formed in the second package is equal to or less than a height of a first formation surface on which the first electrode is formed on the first package substrate, and a difference between the height of the first formation surface and the height of the second formation surface is 500 μm or less.
7 . The high-speed optical transceiver according to claim 1 , wherein the second package is fixed to a support substrate using a conductive adhesive as an underfill agent.
8 . The high-speed optical transceiver according to claim 1 , wherein the first package substrate and the second package are supported by the same support substrate, and heat dissipation surfaces of the first package substrate and the second package are arranged on a side opposite to the support substrate.
9 . The high-speed optical transceiver according to claim 2 , wherein,
when the optical element includes the optical modulating element, a driver IC is integrated with the optical modulating element,
when the optical element includes the light receiving element, a transimpedance amplifier is integrated with the light receiving element,
the high-speed optical transceiver further comprises a Peltier element as a temperature adjustment mechanism, and
the Peltier element dissipates heat to the same side as a side from which the driver IC or the transimpedance amplifier dissipates heat.
10 . The high-speed optical transceiver according to claim 1 , wherein the first package substrate or the second package includes a radio wave absorber in a lid.