| The First Integrated Circuit |
|---|
| Demonstrated by TI in September 1958, this half-inch wide, archaic-looking collection of transistor, capacitor and two resistors mounted on a bar of germanium was the first IC. (Image courtesy of Texas Instruments, Inc.) |
| Seven Years Later - Three Transistors |
|---|
| This amplifier circuit from Siemens was mass produced in 1965. Containing three transistors and five resistors on a 1.5 square millimeter chip, it was a world of sophistication compared to Kilby's invention. (Image courtesy of Siemens AG, www.siemens.com) |
| A Half Century Later - 35 Billion Transistors |
|---|
| Xilinx's Versal chip includes multiple CPUs, RAM and an FPGA section comprising configurable circuits (see FPGA and Versal). |
(also integrated microcircuit), a microminiaturized electronic device, all or some of whose components are inseparably structurally linked and are interconnected electrically. There are two basic types: semiconductor integrated circuits and thin-film integrated circuits.
Semiconductor integrated circuits (Figure 1) are manufactured from extremely pure semiconductor materials (usually silicon or germanium), whose crystal lattice is modified in such a way that individual regions of a crystal become components of a complex circuit. A small chip of crystalline material, with an area of about 1 sq mm, becomes a very complex electronic device, equivalent to a radio engineering unit of 50–100 or more conventional components. Such a device is capable of amplifying or generating signals and of functioning in many other radio engineering applications.

The manufacturing technology of semiconductor integrated circuits makes possible the simultaneous multiple production of large numbers of circuits. This determines the identity of circuit properties. Semiconductor circuits have high reliability because of the use of the planar manufacturing process and a significant reduction in the number of microscopic connections of components in the manufacturing process.
Semiconductor integrated circuits are developing in the direction of increasing concentration of components in the same volume of semiconductor crystal (toward a higher degree of integration). Integrated circuits with hundreds and thousands of components in a single crystal have been developed. In such a case an integrated circuit becomes a complex integrated system. Such a system can be developed and manufactured only with the aid of high-output electronic computers.
Thin-film integrated circuits are made by deposition of various materials at a low pressure (on the order of l X 105 mm of mercury [mm Hg]) as thin films (less than 1 micron [M] thick) or thick films (more than 1 μ thick). The film is deposited on a polished substrate, usually a ceramic, that has been preheated to a particular temperature. Materials used for the film include aluminum, gold, titanium, nichrome, tantalum oxide, silicon monoxide, barium titanate, and tin oxide. To produce integrated circuits with specific functions, multilayer thin-film structures are created by deposition of materials with the required properties on the substrate through a mask or stencil. In such structures one of the layers contains microresistors, another layer contains microcapacitors, and several other layers contain interconnecting current conductors and other components. All components in these layers are interconnected in an arrangement characteristic of the particular electronic device.
Thin-film components are widely used in hybrid integrated circuits (Figure 2). In such systems the passive components (resistors, capacitors, and conductors) are deposited first on the substrate as thin or thick films, and then the active semiconductor microcomponents (nude transistors and diodes) are mounted with the aid of micromanipulators.

Semiconductor and hybrid integrated circuits are complementary in terms of design and electrical characteristics; they can be used simultaneously in identical radioelectronic units. Integrated circuits are mounted in casings that protect them from external influences. Integrated circuits are categorized according to the number of components: first degree of integration (up to 10 components), second degree of integration (10–100), and so on.
The dimensions of the individual components of an integrated circuit are very small (on the order of 0.5-10.Oμ) and are sometimes commensurate with the dimensions of dust particles (1–100 μ). Therefore, the manufacture of integrated circuits is conducted under extremely clean conditions.
There are several trends in the design of integrated circuits, including hybrid circuits, with discrete active components; semiconductor circuits made in a single block of semiconductor material; combined circuits, in which the active components are made in a single block of semiconductor material and the passive components are deposited as thin films; and thin-film circuits, where both the active and passive components are deposited on the substrate as thin films.
I. E. EFTMOV