### 1.2.2 Electronic Materials and Electronic Products

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Electronic Products

| Electronic Materials are what you find inside the components making up electronic products. They consist of some stuff that you cannot easily exchange with something else - not even in principle - without losing the function.
|  | What you can change easily for example, is the material for the box, the housing. Use Al instead of plastic or vice versa for your video recorder - it would still work, needing at most some minor adjustments.
|  | You also may change (in principle) the metal for real wires. Using Au, Ag, or Al instead of - let's say - Cu, makes little difference for the function.
|  | But exchange any material in a "chip" (i.e. in an integrated circuit) with something else (even allowing for minor adjustments) - and that definitely will be the end of your product.
| Let's look at some typical products or product groups that contain electronic materials:
|  | Electronics in general (Computer, TV, Radio, Radar, Microwave, ...).
|  | Flat panel displays (FPD).
|  | Micromechanics and Microsystems (MEMS).
|  | Solar cells.
|  | Lasers (in particular semiconductor Lasers).
|  | Batteries, Accumulators; energy storage systems in general.
|  | Sensors, in particular solid state sensors, that convert whatever they sense directly into a current or a voltage.
|  | Fuel Cells.
|  | Magnetic Memories.

| Looking at Components
| Consider, e.g., a laptop or notebook in more detail. If you take it apart, you find the "high tech" stuff:
|  | Any number of chips, i.e. integrated circuits.
|  | Some quartz oscillators.
|  | A hard disc, i.e. a magnetic memory for the bulk memory.
|  | A reading head for the hard disc that uses the "giant magnetoresistance effect"
|  | A CD ROM, i.e. an optical memory and a semiconductor Laser
|  | A flat-panel display (FPD) using "liqiud crystals", whichis pretty big as a single component, but cannot be subdivided in smaller pieces.
| But there is also "low tech" - or so it seems:
|  | Capacitors and inductors.
|  | Switches, connectors, the keyboard as a unit.
|  | Insulation.
|  | Mechanical stuff like the disk drive, but also the housing.
| Some components betray their key material in their name ("quartz" oscillator) or by common knowledge (who, besides some so-called intellectuals, does not know that the word "chip" is almost a synonym for Silicon?), but for most components we have to look deeper - we must open them up (which will almost always destroy them). What do we find?

| Electronic Materials
| Lets open up a chip. We find
|  | Packaging material - either some polymer blend or ceramics.
|  | A "chip" mostly consisting of Si, but interlaced in an intricate pattern with other materials like P, B, As, SiO2, Si3N4, MoSi2, W, TiN, Al, Cu....
|  | A lead frame - the little pins sticking out of the package - made of some metal alloys.
|  | Tiny wires connecting the leads to the chip or some pretty sophisticated stuff doing this job.
| Now open up the FPD. You will find many materials, the most suspicious beyond what we already found in chips are:
|  | Liquid crystals, some strange liquid stuff.
|  | Amorphous Si.
|  | Indium tin oxide ITO, a transparent electrode.
|  | Plastic foils acting as polarizers.
|  | A plastic (or glass) front and end plate.
| Now lets look at the Laser coming with the CD drive :
|  | You find a complex mix of GaAs, GaAlAs, some other elements, as well as wires and packaging materials.
|  | And all of this is quite different from what you find in the Si chips!
|  | Soon you would find GaN in your Laser diode - and the capacity of your CD memory will quadruple!
| We could continue this, but by now you got the idea:
Progress in Electronic and Communication Technology is driven by Progress in Material Science (and almost nothing else)

© H. Föll (Electronic Materials - Script)