Some questions answered

Terecircuits' unique technology addresses today's needs for rapid time to market with minimal design costs for products which require rigorous optimization of size, power consumption and cost. Its multichip circuits are far smaller and thinner than conventional printed circuit boards. With a form resembling a single ultrathin chip, but with the flexibility to include virtually any type of component at the assembly stage, they meet the needs of today's products with increased performance and reliability with lower total system cost.

Today's printed circuit board systems are a legacy of an industry which goes to the early twentieth century. When transistors came along, it was simple to add them to pre-fabricated PCBs just as was done for vacuum tubes. But what was logical for individual transistors encased in can-style packages is not logical for ICs with millions of planar transistors connected by sub-microscopic metal wiring traces. The result is vast amounts of unused board space, with attendant signal integrity degradation and wasted power.

If it were possible, the ideal electronic system would be a single “chip”, with all elements (transistors, diodes, and passive components) formed in a single set of fabrication steps, all packed together as closely as possible; in other words, the entire system would be an “integrated circuit”. This is not possible for two reasons. First, the yield of such a system would be effectively zero; today's chips are in fact as large as the physics of IC fabrication allow. Second, lithography tools have a finite field of view (just like any camera), which gets smaller as the feature size gets smaller.

What Terecircuits accomplishes is a close approximation to the ideal. Its unique placement technology allows ICs and other components to be placed within microns of each other, in a process that is versatile, physically gentle yet low cost; transforming PCBs into “composite chips”. The components which are normally seen as separate units on a board or flex circuit are now embedded, in close proximity, into a matrix whose coefficient of thermal expansion is nearly the same. Interconnects are formed with the same metal structures as are used in the ICs themselves, eliminating solder which is the dominant source of failure in PCBs.

Component thickness can be reduced to about 25 microns for most silicon ICs, which is thin enough to be highly flexible. Some components, such as MEMS motion sensors, require greater thickness for mechanical protection, but all of the elements of a typical wireless sensor, for example, can be made less than a few hundred microns.

The result is illustrated here with a simple fitness monitor, but the principle can be applied at any scale. fingernail size comparison

Yes. This is simply a different manufacturing process, and does not impact circuit design. In some cases substitution of alternate components with the same function may improve product characteristics such as thinness and flexibility. .

Terecircuits places the components face down on a temporary adhesive (release layer), followed by addition of the embedding material. Conventionally this material is added by injection molding, which is necesssary to get high-viscosity epoxies to penetrate between components, which may be a few hundred μm thick. Injection molding is a high-pressure process in which it is difficult to avoid inhomogeneous forces on the components, and die shift during molding is a major problem limiting positional fidelity. In order to combat it, the dice may be pushed relatively deeply into the temporary adhesive, but this then leads to “die flash”, or discontinuity between chip and embedding medium. These factors further limit the closeness of spacing between components.

Terecircuits replaces the injection molding by a simple dispensing process for the embedding medium, which is made possible by eliminating the geometric constraints of thick dice. Dispensing allows use of thinner temporary adhesive during the embedding process, and results in a smoother surface for interconnect fabrication. An additional benefit is the option to make the matrix (which replaces the usual flex substrate) from more than one type of material, optimizing the entire system for both minimal thermal expansion and effective heat removal.

Terecircuits' technology development is supervised by professionals with decades of experience in management of high- volume, complex microelectronic production with demanding reliability specifications. You may be assured that we will provide the quality you expect, and will document it as requested.