Vertical integration of high-Q silicon nitride microresonators into silicon-on-insulator platform

Abstract

We demonstrate a vertical integration of high-Q silicon nitride microresonators into the silicon-on-insulator platform for applications at the telecommunication wavelengths. Low-loss silicon nitride films with a thickness of 400 nm are successfully grown, enabling compact silicon nitride microresonators with ultra-high intrinsic Qs (~ 6 × 10(6) for 60 μm radius and ~ 2 × 10(7) for 240 μm radius). The coupling between the silicon nitride microresonator and the underneath silicon waveguide is based on evanescent coupling with silicon dioxide as buffer. Selective coupling to a desired radial mode of the silicon nitride microresonator is also achievable using a pulley coupling scheme. In this work, a 60-μm-radius silicon nitride microresonator has been successfully integrated into the silicon-on-insulator platform, showing a single-mode operation with an intrinsic Q of 2 × 10(6).

Fabrication and characterization of on-chip silicon nitride microdisk integrated with colloidal quantum dots

“…In fact, this tunability has already been studied in passive SiN disks [2,3,16]. In active devices it is of practical importance, e.g.…”

“…Silicon nitride (SiN), due to its fairly high optical index (~2.0), broad operating wavelength range, and compatibility with complementary metal-oxide-semiconductor (CMOS) processing technology, is a promising material as the basis for an integrated optics platform [1][2][3][4][5].…”

Low-loss silicon nitride waveguide hybridly integrated with colloidal quantum dots

“…Various plasma chemistries, such as CF 4 [1], CF 4 /CHF 3 [2], C 4 F 8 /SF 6 /H 2 [7], CHF 3 /O 2 [8], and CF 4 /H 2 [16], have already been used to obtain anisotropic etching in SiN. However, unlike what is the case for SiN-films deposited in a single step, due to the considerable difference in material density the etching behavior between H-SiN and L-SiN deposited on top of each other can vary a lot.…”

“…Silicon nitride (SiN) exhibits transparency from the visible to the mid-infrared and has a fairly high optical index (~2.0), making it suitable for various photonic applications including integrated photonic circuits [1][2][3][4], nonlinear optics [5], high quality optical cavities [6][7][8], and on-chip biosensing [9]. On the other hand, because of its dielectric nature, the SiN platform is thus far limited to passive devices and a light source such as a laser or a single photon emitter integrated in this platform is highly desired.…”

On-chip hybrid integration of silicon nitride microdisk with colloidal quantum dots

“…Given its moderate optical index (~2.0), broad operating wavelength range and low-loss, silicon nitride (SiN) photonics is a promising platform for various applications including integrated photonic circuits [1], nonlinear optics [2], and onchip biosensing [3]. On the other hand, because of its dielectric nature, SiN devices have thus far been limited to passive functionalities and an optically active SiN photonics platform is highly desired.…”