A novel wafer dicing method using metal-assisted chemical etching

Effect of additives on preparation of vertical holes in Si substrate using metal-assisted chemical etching

“…According to previous reports, there are mainly three routes for the mass transfer of chemicals, which are penetration of and diffusion through the catalyst layer, a path through the edge of catalyst layer, and diffusion along the interface. 17,34) In the present case, the diffusion of chemicals from the edge of the catalyst is the dominant route because the sputtered catalyst film is dense, which suppresses diffusion through the film. Therefore, etching primarily occurs at the Si surface under the edge parts of the catalyst, and the etching rate of Si is gradually decreased with increasing distance from the edge.…”

“…Recently, metal-assisted chemical etching (MacEtch) has attracted attention for the fabrication of nano/microscale structures in Si substrates, such as nanowires and nanohole array. [13][14][15][16][17][18][19][20][21] In this method, a noble metal is used as a catalyst, and only Si is selectively etched under the catalyst in the etching solution. 22) Generally, Au is used as this catalyst, and the Au can be removed by nitrohydrochloric, iodine or cyanogen systems after the MacEtch process.…”

“…There have been several reports on the formation of microscale patterns using MacEtch. [17][18][19] However, it is difficult to obtain deep and straight vertical holes using the MacEtch process due to variations in the etching direction for prolonged processes. Figures 1(a) and 1(b) show cross-sectional SEM images of Si holes obtained using the MacEtch process.…”

General corrosion during metal-assisted etching of n-type silicon using different metal catalysts of silver, gold, and platinum

“…Fabrication of high-aspect-ratio structures has been studied for the production of micro electro mechanical systems (MEMS), 11 through-silicon via (TSV), 12,13 and X-ray diffractive optics 14,15 as well as for wafer dicing. 16 Complex 3D structures, e.g. helical pores, 17,18 spiraling pillars created by grid-shaped and star-shaped catalysts, 19 nanocone arrays, 20 and zigzag wires, 21 have also been reported.…”

Effect of a metal interlayer under Au catalyst for the preparation of microscale holes in Si substrate by metal-assisted chemical etching

“…Several papers have been already reported on the formation of microscale patterning using MacEtch. [18][19][20] A Ti interlayer between Au catalyst layer and Si substrate was previously introduced as a conventional adhesion layer, and these paper reported that the Ti interlayer helped to eliminate the unnecessary lateral Si etching during MacEtch. 21,22) However, the detail of role for Ti interlayer in MacEtch process has not been fully understood.…”