Multi-user Equipment approved in grant 2018/03474-7: chemical-mechanical polishing machine (CMP)

• Grant number: 20/01987-7
• Support Opportunities: Multi-user Equipment Program
• Duration: September 01, 2020 - August 31, 2027
• Field of knowledge: Interdisciplinary Subjects
• Principal Investigator: Felippe Alexandre Silva Barbosa
• Grantee: Felippe Alexandre Silva Barbosa
• Host Institution: Centro de Componentes Semicondutores (CCS). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 18/03474-7 - Nonclassical states of light on chip, AP.JP
• EMU web page: Página do Equipamento Multiusuário não informada
• Type of equipment: Processos Físicos - Modificação superfícies – etching - Mecânica
• Manufacturer: Fabricante não informado
• Model: Modelo não informado

Abstract

The main applications of the mechanical chemical polishing machine (CMP) are the planarization of surfaces and the control of roughness (polishing). In the context of integrated photonics and electronics, this equipment is mainly used for surface planarization, which is used in various contexts such as preparing samples for wafer bonding and reducing roughness on thin film surfaces. For example, the CMP has recently been used to decrease the roughness of lower and upper surfaces of silicon nitride optical cavities by polishing the top surfaces of both the silicon nitride thin film as well as the silicon oxide substrate on which it was deposited. This procedure was crucial for breaking the 10 million barrier of intrinsic quality factor for silicon nitride cavities. The intrinsic quality factor is a measure of propagation losses and part of these losses occur due to surface roughness. These intrinsic losses are one of the most important parameters to be optimized in the context of nonlinear optics because they determine the lowest threshold power that can be achieved in a specific optical cavity. In the context of quantum optics, and more specifically in the preparation of squeezed and entangled quantum states, the ratio of the internal losses to the coupling efficiency with the external world (also called the ideality factor) determines the noise compression factor for the squeezed states and the amount of entanglement for the entangled states. In principle, intrinsic quality factors of the order of millions can be obtained without polishing the upper and lower surfaces. But above this point, the surface roughness becomes the main limiting factor. Both silicon nitride and silicon oxide deposited at Centro de Componentes Semicondutores (CCS) have a surface roughness of the order of nanometers, which can be improved by using the CMP by a factor 10. The acquisition of this equipment will allow the optical quality of the silicon nitride produced in the CCS to be equal to those obtained in the research groups of excellence in the area of integrated photonics. This acquisition of this equipment will allow a for huge leap in the quality of scientific and technological reserach based on this type of material and will allow for several groups at Unicamp and surrounding institutions to broaden the scope of their respective research. (AU)