Etch holes

Here, L total is the depth of the etched hole per pulse and is assumed to be the sum of photochemical and photothermal contributions, Tphoto and Thermal, respectively 0Ceff is the effective photon absorption coefficient of the medium and can vary with laser emission characteristics, e g., photon density Fis the incident laser fluence Fth is the medium s threshold fluence A and F are the effective frequency factor with units of pm/pulse and the effective activation energy with units of J/cm2, respectively, for the zeroth-order thermal rate constant F0, comparable in magnitude to Fth, is important only at low fluences.64 Equation (5) is obtained after assuming that the polymer temperature T in the laser-exposed region of mass mp and the thermal rate constant k are given, respectively, as... 

For a (110) wafer the geometries of the etched holes are different because the four sets of 111 planes which form the sidewalls of the cavities are not equivalent. Vertical grooves with a high aspect ratio can be obtained by etching a masked (110) wafer because two sets of (111) planes are vertical to the (110) surface... 

Fig. 32 (a) Anisotropically etched holes through small openings of different... 

Plasma Etching, Fig. 5 Schematic diagram of the STS ASE procedure (a) passivation step after one cycle (b) the etching step after one cycle, i.e., the second etching (c) profile after four cycles and (d) cross-sectional SEM micrograph of the etched holes with scalloped surface... 

Structure. Figure 23.27 shows the structure of DYCOstrate.The core material can be polyimide film with plasma-etched holes, drilled epoxy fiberglass, or other plasma-etchable materials such as liquid crystal polymers. Multiple layers can be built up to increase density with the resulting buried and blind vias, but two-sided DYCOstrate structures are also used in products because of the very high density that 0.075 mm through holes allow. 

Another type of very accurate sieving surface is made by etching holes in a thin steel surface. These etched hole sieving surfaces are available from the Veco Company [21]. 

To control the growth of the diameter of a whisker at the anode, we can sputter a thin coating of quartz over the entire Sn strip with an etched hole of a given diameter at the anode. With an applied current density, a whisker can be pushed out from the hole at the anode. We can measure the growth rate and the volume of the whisker as a function of current density, tem-... 

Figure 8.10 Through-wafer etch holes to enable back-side release. The backside etch holes eliminate the need for etch holes in the Poly2 mirror membrane. (Reprinted with permission from IEEE Journal of Selected Topics in Quantum Electronics, Microelectromechanical deformable mirrors, 1967 IEEE.)...

Release silicon dioxide through etch holes in polyl and poly2... 

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