Fine lines

There has been a continual increase in size and complexity of PCBs with a concurrent reduction in conductor and hole dimensions. Conductors can be less than 250 p.m wide some boards have conductors less than 75 pm wide. Multilayer boards greater than 2.5 mm thick having hole sizes less than 250 pm are being produced. This trend may, however, eventually cause the demise of the subtractive process. It is difficult to etch such fine lines using 35-pm copper foils, though foils as thin as 5 pm are now available. It is also difficult to electroplate holes having high aspect ratio. These factors may shift production to the semiadditive or fully additive processes. 

Resists used to define circuit patterns are radiation-sensitive and may be either positive- or negative-working. As a result of the fine lines, there has been movement away from optical Hthography and iato the mid- or deep-uv regioas. Developmeatal work has also beea focused oa electroa beam, x-ray, and ion-beam exposure devices and resists (9,10). 

The influence of gravity on a sediment can be shown schematically by the fine line of Figure 5, where it is shown to have the effect of tilting the entire... 

Using an 8-in. Nichrome wire strip connected with springs to a variac, organic decomposition can be carried out in a very fine line to locate zones. The resulting carbon is small in quantity and will not interfere in subsequent elutions. 

In this activity, you will collect data and draw a line graph. Be certain that your graph is neat and easy to read. Use a sharp pencil to establish points and draw a fine line. 

Metal Casting Techniques. Many ancient cast metal objects were made by the cire perdue (lost wax) casting process, which involves pouring molten metal into a one-piece mold and letting it solidify modem fakes are usually cast in two halves that are then joined. A casting fin, or a fine line of filed solder on a cast object, usually reveals that the casting is modem. 

FIGURE 7.3 Breakdown of perturbation-theory approach for Cun(H20)6 in L-band. The spectrum of the elongated CuOs octahedron (upper trace) is simulated (lower trace) with the approximative resonance condition defined in Equation 5.18. There is no fit of the first hyper-fine line at low field (Hagen 1982a). 

Fig. 5 (a) Molecular arrangements viewed along the molecular planes, (b) Packing diagram viewed along the be plane in [(ppy)Au(C8H4S8)]. Fine lines show sulfur-sulfur contacts (<3.7 A) (Reprinted with permission from [26]. Copyright 2003 Elsevier)... 

Fig. 7 Packing diagrams of (a) [(ppy)Au(C8H4S8)]2[PF6] (PF6 salt) and (b) [(ppy)Au(C8H4 S602)]2[BF4] (BF4 salt) viewed along the a axis. Side-views of the columns in the (c) PF6 salt and (d) BF4 salt. Molecular arrangements of two crystallographically independent molecules within the column of (e) PF6 salt and (f) BF4 salt. Fine lines indicate S—S contacts shorter than 3.7 A. Dashed lines indicate O—H contacts within the range of 2.62-2.70 A. (Reprinted with permission from [35]. Copyright 2008 American Chemical Society)...

The thread between innocence and guilt was the fine line of absolute certainty. Since there was a fantastic possibility that Hitler might have turned back had Poland resisted his demands, the de-... 

Fig. 14.9. Variation of surface potential (mV) with pH for a hydrous ferric oxide surface in contact at 25 °C with a 0.1 molal NaCl solution (bold line) and a more complex solution (fine line) that also contains Ca, SO4, Hg, Cr, As, and Zn.

Fig. 15.6. Effects on pH (top) and C02 fugacity (bottom) of reacting HC1 into a fluid not in contact with calcite (fine lines) and with the same fluid when it maintains equilibrium with calcite over the reaction path (bold lines).

Fig. 15.10. Calculated effects on pH of reacting sodium hydroxide into an initially acidic solution that is either closed to mass transfer (fine line) or in equilibrium with atmospheric C02 (bold line).

Fig. 16.1. Results of reacting quartz sand at 100°C with deionized water, calculated according to a kinetic rate law. Top diagram shows how the saturation state Q/K of quartz varies with time bottom plot shows change in amount (mmol) of quartz in system (bold line). The slope of the tangent to the curve (fine line) is the instantaneous reaction rate, the negative of the dissolution rate, shown at one day of reaction.

Fig. 19.2. Isotopic composition (bold lines) of dolomite formed by reaction between a limestone and migrating groundwater, assuming that minerals maintain isotopic equilibrium over the simulation. Fine lines show results of simulation holding minerals segregated from isotopic exchange, as already presented (Fig. 19.1).

Fig. 20.3. Transport model of the migration of a chemical species through an aquifer, calculated for two Peclet numbers, Pe. Species is not present initially, but from t = 0 to t = 2 years recharge at the left boundary contains the species at concentration C0. After this interval, concentration in recharge returns to zero. Fine line shows result for dispersivity aL of 0.03 m, corresponding to a P6clet number on the scale of the aquifer (1000 m) of 33 000 bold line shows results for oil = 3 m, or Pe = 330.

Fig. 21.2. Transport of benzene within an aerobic aquifer through which groundwater is flowing at a velocity vx of 100 m yr-1, calculated accounting for biodegradation, assuming biomass in the aquifer remains constant. Benzene recharges the aquifer at 1 mg kg-1 concentration from t = 0 to t = 2 years, after which time clean water enters the aquifer. Fine lines show transport calculated assuming the species is non-reactive, for comparison.

Fig. 21.3. Transport of benzene within an aerobic aquifer, as depicted in Figure 21.2, calculated assuming the species not only biodegrades, but sorbs to organic matter in the aquifer. Benzene in the simulation sorbs with a distribution coefficient of 0.16 x 10-3 mol (g sediment)-1, equivalent to a retardation factor R of 2. Fine lines show non-reactive case.

Fig. 22.1. Calculated mineralogical consequences of cooling (bold lines) the Albigeois ore fluid from 175 °C to 125 °C, and of quenching it (fine line) with 125 °C water.

Fig. 23.1. Variation in pH in a computer simulation of sampling, cooling, and then reheating a hypothetical geothermal fluid. Bold line shows path followed when system is held closed fine lines show variations in pH when fluid is allowed to degas CO2 as it cools.

Fig. 23.4. Mineral saturation indices (log Q/K) over the course of simulating the reheating of a hypothetical geothermal fluid. Bold lines show indices for minerals assumed to be present in the initial formation fine lines show values for other minerals. Dashed line marks sampling temperature (250 °C).

Fig. 26.3. Silica concentration (bold lines) in a fluid packet that cools from 300 °C as it flows along a quartz-lined fracture of 10 cm aperture, calculated assuming differing traversal times At. Fine lines show solubilities of the silica polymorphs quartz, cristobalite, and amorphous silica.

Fig. 31.1. Calculated variation in pH during reaction of pyrite with a hypothetical ground-water at 25 °C, assuming that the fluid is isolated from (fine line) and in contact with (bold line) atmospheric oxygen.

I ve had to learn to mask my symptoms to a point so that I can even function in the world. There is such a fine line between masking a little bit so it doesn t hurt your health, and masking so much that it does hurt your health. When I was going to bars, I masked way too much and it really hurt me. 

The 193 nm light from a Questek ArF excimer laser was used to obtain sensitivity data by exposing 1 cm2 areas. Fine line patterning with 193 nm light was done on a Leitz IMS exposure apparatus with either 15X or 36X reflective objectives. The fluence was varied from 0.1 to 100 mJ/cm2/pulse. All exposures at 248 nm were conducted on a deep-UV stepper(12) with a NA = 0.38 lens, 5X reduction, a minimum feature size of 0.4 pm and a fluence of -0.3 mJ/cm2/pulse. 

Optical Exposure. Multicomponent LB films were prepared from solutions of novolac/PAC varying in concentration from 5-50 wt% PAC, and transferred at 2.5 -10 dyn/cm. The films were composed of 15 - 20 monolayers, with an average film thickness of 30 nm, as measured by ellipsometry. Exposures were performed with a Canon FP-141 4 1 stepper (primarily g-line exposure) at an exposure setting of 5.2 and with a fine line test reticle that contains line/space patterns from 20 to 1 pm (40 to 2 pm pitch). They then were then developed in 0.1 - 0.2 M KOH, depending on the PAC content The wafers received a 20 min 120°C post development bake to improve adhesion to the Cr. Finally, the Cr was etched in Cyantek CR-14 chromium etchant, and the resist and Cr images were examined by SEM. 

A variety of alternating copolymers based on H-allyl- and N-(3-ethynylphenyl)maleimides, with substituted styrenes and vinyl ethers, have been prepared and their response to x-ray irradiation studied. Broadband and monochromatic x-ray exposures were conducted at the Stanford Synchrotron Radiation Laboratory. Sensitivities were observed to correlate with mass absorption coefficients of the copolymers and were found to be as high as 5-10 mJ/cm2. Preliminary fine line lithographic studies indicate 0.5 ion resolution capabilities. 

---