Design and analysis of 3D stacked optoelectronics on optical printed circuit boards

Abstract

In this study, a low-cost (with bare chips) and high (optical, electrical, and thermal) performance optoelectronic system with a data rate of 10Gbps is designed and analyzed. This system consists of a rigid printed circuit board (PCB) made of FR4 material with an optical polymer waveguide, a vertical cavity surface emitted laser (VCSEL), a driver chip, a 16:1 serializer, a photo-diode detector, a Trans-Impedance Amplifier (TIA), a 1:16 deserializer, and heat spreaders. The bare VCSEL, driver chip, and serializer chip are stacked with wire bonds and then solder jointed on one end of the optical polymer waveguide on the PCB via Cu posts. Similarly, the bare photo-diode detector, TIA chip, and deserializer chip are stacked with wire bonds and then solder jointed on the other end of the waveguide on the PCB via Cu posts. Because the devices in the 3D stacking system are made with different materials, the stresses due to the thermal expansion mismatch among various parts of the system are determined.

Embedded 3D Hybrid IC Integration System-in-Package (SiP) for Opto-Electronic Interconnects in Organic Substrates

“…One of the key technologies that helps to make these product design goals possible is to have a bare chip on optical PCB [3,4]. It is even better to stack up a few chips (in three dimensions) on the board to enhance performance and save more cost and realestate [5]. In order to make super-thin and super-light products, e.g., mobile phones, the waveguide [6][7][8] and chips should be embedded in the optical PCB, which is the focus of this investigation.…”

“…This helps to increase the mechanical reliability of the circuit and minimize assembly requirements. Figure 2 shows a low-cost (with bare chips) and high (optical, electrical, and thermal) performance optoelectronic system with a data rate of 10Gbps is designed and analyzed [5]. This system consists of a rigid PCB made of FR4 material with an optical polymer waveguide, a VCSEL, a driver chip, a 16:1 serializer, a photo-diode detector, a Trans-Impedance Amplifier (TIA), a 1:16 deserializer, and heat spreaders.…”

“…Similarly, the bare photo-diode detector, TIA chip, and deserializer chip are stacked with wire bonds and then solder jointed on the other end of the waveguide on the PCB via Cu posts. Because the devices in the 3D stacking system are made with different materials, the stresses due to the thermal expansion mismatch among various parts of the system have been determined [5]. Figure 3 shows a single channel OECB with embedded waveguide using traditional PCB manufacturing process [6][7][8].…”