Silicon first prototype

The first prototype transistor (a point-contact semiconductor amplifier ), built by Bardeen and Brattain at Bell Laboratories in 1947 (a), is a far cry from today s silicon chips, packed with miniaturized semiconductor components (6)... 

The first prototype micromixer was a roughly 1 mm thick silicon plate with the dimensions of ca. 17 X 30 mm (Fig. 15.4). The hrst trivial task to be solved was how to introduce reagents and organic solvents into this micromixer. The first approach was to glue a hypodermic needle onto the silicon chip. The resulting construction was fairly fragile and had to be stabilized by a polymer cast. 

We wait in suspense for a report in the near future that the authors can suggest a solution to these problems. If this is the case it is foreseeable that light-driven parallel synthesizer machines, similar to the present peptide and DNA synthesis machines with soon revolutionize many university and pharmacetical research laboratories. The site of the Affymax Research Institute of the authors in Silicon Valley will, of course, not hinder the development of the first prototype of the commercial machines. 

Silicon-based pDMFC and pDEFC first prototypes were fabricated using MEMS micromachining technology, which allows micro flow channels having width and deepness in the order of 100-200 pm and dehver a maximum power density of up to 14 mW.cm for active methanol feed [61], and 8 mW.cm for passive ethanol feed [62] at room temperature. 

The ISFET-based integrated coulometric sensor-actuator system was introduced in 1985 [154] in order to facilitate in situ calibration of ISFETs. The essential components of a prototype sensor based on this operational principle are shown in Fig. 4.20.B. The system was built by integrating a large noble-metal actuator electrode and a counter-electrode in a piece of silicon. A window in the actuator electrode was etched to receive the gate of the ISFET, which functioned as a pH indicator. The flow-through cell was constructed by sealing a silicon cover with an etched cavity of the chip. The system operation resembles that of a conventional coulometric titration system very closely. The sample was first injected into the cavity and the... 

The test data show that the conditions required to completely clean the coupon of silicone oil are a pressure of 105 bar at a temperature of 45°C with an impeller speed of 1000 rpm. To scale up this process for use with actual parts contaminated with a similar material, we must first decide which criteria to include for achieving similitude. Since temperature and pressure are intrinsic values that do not rely on any other aspect of the prototype design, except that it must be able to hold the desired pressure at the desired temperature, the mechanisms governing mass transfer and agitation become paramount. 

As a first step in our study, we decided to assess our idea of microfabricated nib tips with simple structures based on the negative photoresist SU-8. Structures having a 2/2 D topology were fabricated on a silicon wafer support 11 it should be noted that the nib feature is not completely planar as the tip of the nib tended to point upwards due to stress in the thick SU-8 polymer layer. The nib structure is composed of a reservoir feature, a capillary slot leading the liquid to the tip of the nib where electrospray occurs upon HV application. These first nib prototypes have a microfluidic capillary slot with a width of around 20 pm. Figure 5.2 shows a scanning electron micrograph of a microfabricated nib tip in SU-8 and supported on a silicon support. 

Compounds containing silicon-silicon bonds, the so-called oligosilylanions, are of special interest among the silylanions. The prototypical compound, Li[Si(SiMe3)3], was first prepared by Gilman et al. by treatment of Si(SiMe3)4 with methyllithium (Eq. 4). ... 

This new type of solar cells has many advantages in comparison with semiconductor solar batteries, they are much less expensive as their silicon counterparts, since only cheap materials are used. Their production process is relatively simple and is environmental friendly. The main disadvantage of the first DSSC prototypes was the use of a liquid electrolyte solution that required a thorough hermetization of the cell. Moreover the liquid state of the electrolyte made the cell sensitive to temperature changes. At very low temperatures the electrode froze and ice crystals could destroy other parts of the cell. At high temperatures the expanding electrolyte could weaken the cell s hermetization. 

A review of the history of the development of silicon MEMS shows that production of single devices for mass markets has been the dominant pattern in commercialization. The first products were pressure sensors for the automobile mass market. Next came the accelerometers for the same market, and more recently optical switches and ink-jet printheads. Similar parallels can be seen in the development of conducting polymer devices. Of the wide variety of prototype sensors, actuators, and electrical components that have been demonstrated over the past 10-15 years, only polymer LEDs have been completely commercialized. Smart systems utilizing MEMS and conjugated polymers, which were anticipated to be the killer app, have yet to make their appearance. 

---