Silicon Micro-Channel Definition via ICP-RIE Plasma Etching Process Using Different Aluminum Hardmasks

Autor(es)

Alvarez, Hugo S. ^[1] ; Cioldin, Frederico H. ^[2] ; Silva, Audrey R. ^[2] ; Espinola, Luana C. J. ^[2] ; Vaz, Alfredo R. ^[2] ; Diniz, Jose A. ^[1]

Afiliação do(s) autor(es)

^[1] UNICAMP FEEC, DSIF, BR-13081970 Sao Paulo - Brazil

^[2] Univ Estadual Campinas, Ctr Componentes Semicond & Nanotecnol, BR-13083970 Campinas - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF MICROELECTROMECHANICAL SYSTEMS; v. 30, n. 4, p. 668-674, AUG 2021.
• Citações Web of Science: 0

Resumo

In this work, thermally evaporated aluminum (Al) was used as hardmask (HM) to obtain silicon microchannels (SiMCs), using an Inductively Coupled Plasma - Reactive Ion Etching (ICP-RIE) system, in SF6/Ar gas mixture environment. The channel depth must be greater than 50 mu m, with a high aspect ratio. For this, Al HM lines were defined by photolithography and by Al wet etching on a silicon substrate. To improve the resistance against the ICP-RIE etching process, the Al HMs were treated with four different conditions: i) Al HM without treatment step (control sample); ii) with plasma nitridation (AlN/Al structure); iii) with thermal annealing (annealed Al film); iv) with plasma nitridation and annealing (annealed AlN/Al structure). After 100 min of ICP-RIE etching process, SiMC with depths of 90.6 mu m, 95 mu m, 91.2 mu m, and 109 mu m, respectively, were measured using a scan profiler system. As the main result, the annealed AlN/Al structure presented a high resistance against the ICP-RIE etching for 100 minutes. Furthermore, Scanning Electron Microscopy (SEM) images indicate an etch uniformity on the walls and bottom of the channels for all the samples. This parameter is a mandatory requirement to obtain the integrated microchannel liquid-cooling technology for heat sinks in photovoltaic cells and Complementary Metal-Oxide-Semiconductor microprocessors. (AU)

• Processo FAPESP: 16/09509-1 - Processos de transferência de calor com mudança de fase de elevado desempenho aplicados ao aproveitamento de energia solar
• Beneficiário: Gherhardt Ribatski
• Modalidade de apoio: Auxílio à Pesquisa - Temático