Magnesium (Mg) is a chemical element with atomic number 12 and belongs to the second column (Group 2, or alkaline earth metals) of the periodic table. It is a light metal which reacts violently with all elements from the chalcogen group. It forms semiconductor compounds with oxygen, sulfur, selenium and tellurium. The energy gap in those compounds is bigger than in CdTe or ZnTe. In the two dimensional AIIBVI structures prepared by the Molecular Beam Epitaxy (MBE) method magnesium is used to create an energy barrier. In the AIIIBV semiconductor compounds, such as GaN, Mg is an acceptor which allows to make light emitting p-n junctions.
Magnesium oxide (MgO) is a semiconductor with a wide gap and semi-insulating properties. A very thin semi-insulating MgO layer between two metallic ferromagnetic layers is used in “magnetic tunnel junction”. Due to its very low work function Mg could also be used to make cathods techniques in the Organic Light Emitting Diodes (OLEDs). In the last two cases sputtering techniques are used.
The Mg targets with 2 inch diameters are used in laboratories, whereas industry applications need 3 inch Mg targets. Targets with 4 N (99,99%) purity are available on the market, but those with 5N purity were not produced until now.
Ultrapure Magnesium 12Mg24.312 (m6N; t5N8)
|PIECES||≈ (10x20, 10x10, 10x5, ...) mm2 plates, ~3 mm thick|
|INGOTS||∅=6 mm, 10 mm
∅=15 mm, 20 mm, 25 mm
|10 to 25 mm length
20 to 30 mm length
|TARGETS||∅=25,4 mm (1 inch)||3 to 35 mm thick|
|TARGETS||∅ > 1 inch||3 to 35 mm thick|
|RESULTS OF ANALYSES BY THE SPARK SOURCE MASS SPECTROMETRY (SSMS)
AND GLOW DISCHARGE MASS SPECTROMETRY (GDMS) (IN PPM wt):
|Li < 0.01||Na < 0.05||P < 0.03|
|B < 0.02||Al ≈ 0.05||S ≈ 0.3|
|F < 0.05||Si ≈ 0.05||Cl< 0.2|
|K ≈ 0.05||Fe ≈ 0.05||Ga < 0.01|
|Ca ≈ 0.05||Cu < 0.05||Ge < 0.05|
|Mn < 0.05||Zn ≈ 0.7||As < 0.05|
|Ru < 0.5||Sn < 0.05||Ta < 1|
Note: density of Mg is ~ 1.7 g/cm3.