Loss assessment in random crystal polarity gallium phosphide microdisks grown on silicon

Abstract

III-V semiconductors grown on silicon recently appeared as a promising platform to decrease the cost of photonic components and circuits. For nonlinear optics, specific features of the III-V crystal arising from the growth on the nonpolar Si substrate and called antiphase domains (APDs) offer a unique way to engineer the second-order properties of the semiconductor compound. Here we demonstrate the fabrication of microdisk resonators at the interface between a gallium-phosphide layer and its silicon substrate. The analysis of the whispering gallery mode quality factors in the devices allows the quantitative assessment of losses induced by a controlled distribution of APDs in the GaP layer and demonstrates the relevance of such a platform for the development of polarity-engineered III-V nonlinear photonic devices on silicon.

Crystal Phase Control during Epitaxial Hybridization of III‐V Semiconductors with Silicon

“…[25,26] Threading APBs are therefore a critical issue as far as they introduce efficient vertical electrical path within the III-V heterostructure, thereby killing the performances of any p-n junction device. [25,27] Engineering the APBs generation and propagation at the early stages of the III-V growth on Si is thus the only way to fully benefit from the ultimate properties of integrated III-V semiconductors and a major prerequisite for the successful monolithic integration of III-V optoelectronic devices on Si photonic platforms [28,29] or III-V/Si energy harvesting devices. [5] In 1987, Kroemer [30] gave a first description of APBs generation, correlating the domain distribution and the local step structure of the initial Si surface.…”

Epitaxial III–V/Si Vertical Heterostructures with Hybrid 2D‐Semimetal/Semiconductor Ambipolar and Photoactive Properties

“…The surface appears rough, with visible inclusions of anti‐phase materials in the main phase matrix. To further identify and study the local properties of the singularities, independently of the roughness and faceting induced by emerging APBs, [ 19 ] an APB developing treatment (combining chemical mechanical polishing (CMP) and etching processes, [ 20 ] as described in the Supporting Information) was used. A typical SEM image of the same sample after APB developing treatment is given in the inset of Figure 1b, showing the nice improvement of the surface smoothness in individual single‐phase domains (below 3 nm root‐mean‐square roughness), and the clear identification of emerging APBs distribution (see also Figure S2, Supporting Information, for a SEM image at a larger scale).…”

“…Recently, large efforts were dedicated to the understanding of the formation [16] and propagation [17] of APBs during the epitaxial growth. With this description, early burying of the antiphase domains (APDs) [18,19] for lasers and photo electro chemical (PEC) devices or controlled emerging APB density for non-linear photonics [20] were achieved, showing the fine control of the crystal growth achieved. Beyond materials developments, physical properties of the specific stoichiometric APBs (with equal numbers of III-III and V-V bonds within the same APB) were recently clarified.…”

Continuous-Wave Second-Harmonic Generation in Orientation-Patterned GaP Waveguides at Telecom Wavelengths

“…A final polishing step is, therefore, implemented (Step 6). After this chemical mechanical polishing (CMP) step, the RMS surface roughness is reduced to 1 nm 18 . Finally, the HAADF-STEM cross-section in Figure 1 (c) reveals one more important feature of the fabrication process proposed in the present contribution: the domain boundaries between inverse and direct GaP are almost perfectly parallel to the {0 0 1} direction, all throughout the thickness of the OP-GaP crystal, yielding a 95 % domain fidelity over the region observed in TEM.…”

“…Outside this range, frequency conversion in PPLN is, however, hampered by multi-photon or free-carrier absorption present in many oxides. Furthermore, while significant advances have been made, these oxide crystals are not as readily integrated in Si-photonics as group IV or III-V semiconductors [2][3][4][5] .…”