Magnetic bubble memories

Garnets are important gems, abrasives, microwave systems components, magnetic bubble memories, and laser hosts. For the latter, yttrium aluminum garnet is the most important. It also plays an important role in aircraft turbines where it forms a protective coating on the turbine blades. 

Figure 9.11 Magnetic bubble memory schematic domains of reversed polarity (bubbles) are induced in the thin ferromagnetic garnet film.

Data storage via magnetic bubble memories used thin films of ... 

Important is the use of light rare earth elonents for production of hard magnetic materials. Most prominent are alloys of samarium with cobalt in the atomic ratio 1 5 or 2 17. It may also be assumed that in further development of these materials on a larger scale that praseodymium, neodymium, lanthanum and also individual heavy rare ecu h elements will be used to achieve particular effects. Interesting is the development of magnetic bubble memories based on gadolinium-galliiimrgarnets. 

Rare earth substituted garnet films for magnetic bubble memory applications... 

The manufacture of thin film products does not only apply to the making of integrated circuits but also magnetic bubble memories, thin film recording heads, tapes and disks. The physical and chemical processes carried out involve heat and mass transfer, momentum transfer, surface phenomena, high temperature chemistry, radiation, etc. Although the material discussed in this book focuses on the manufacture and fundamentals of integrated circuits, many of the basics are applicable to the fabrication of other thin film devices. 

Yttrium aluminum garnet (YAG), Magnetic bubble memory devices... 

Liquid phase epitaxy (LPE) was used for forming thin garnet films for magnetic bubble memories. Describe the basic principles behind this technique. Would sputtering or evaporation be good alternative techniques for such films Explain how you arrived at your answer. 

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