Low Threshold Current Density Operation of a GaInAsP/Si Hybrid Laser Prepared by Low-Temperature N₂ Plasma Activated Bonding

Abstract

The integration of III–V active devices on a Si platform utilizing direct bonding is an attractive way to realize large-scale photonic integrated circuits. Because plasma activated bonding (PAB) is expected to have a higher bonding strength at a lower heating temperature as compared to conventional bonding methods, PAB is attractive for the reduction of non-radiative recombination centers in the III–V active region caused by thermal expansion during the bonding process. A GaInAsP/Si hybrid laser was fabricated with low-temperature (150 °C) N2 PAB, and a low threshold current density of 850 A/cm2 (170 A/cm2 per quantum well) was obtained.

Direct Semiconductor Wafer Bonding in Non-Cleanroom Environment: Understanding the Environmental Influences on Bonding

“…Presumably, the obtained bonding strength is not affected by the variations in the process conditions; however, some random fluctuations are observed. We achieved a bonding interfacial mechanical strength as high as 1.2 MPa, which comparable to the state-of-the-art reported data obtained in cleanrooms from leading research teams in the field, 22,23 and sufficient stability for device applications. As shown in the typical cross-sectional SEM image of the bonded Si/Si interface in Figure 13, the wafers are firmly and uniformly contacting each other with a sufficient mechanical stability to endure the cleavage of the bonded-pair sample.…”

Review of Low‐Temperature Bonding Technologies and Their Application in Optoelectronic Devices

“…Silicon photonics, which actively uses Si as photonics devices for the purpose of optical wiring in LSI, has been attracting attention. Evanescent coupling lasers have been developed in which bonding of the SOI wafer used for the Si wiring waveguides with an InP laser wafer is achieved by low‐temperature bonding techniques such as plasma activation bonding or surface activated bonding .…”

Determination of the characteristics of the metallic bonding interface and the bonding strength of a Cu interlayer by using atomic force microscopy

“…Most researchers have typically focused on dry processes such as plasma surface activation and electron beam lithography [19][20][21]. However, as the wafers increase in size, the dry process becomes limited by its high cost.…”