	US 12,448,335 B2
	Magnesium oxide sputtering target and method of making same
Eugene Y. Ivanov, Grove City, OH (US); and Christopher M. Jaworski, Grove City, OH (US)
Assigned to TOSOH SMD, INC., Grove City, OH (US)
Appl. No. 16/310,864
Filed by TOSOH SMD, INC., Grove City, OH (US)
PCT Filed Jul. 5, 2017, PCT No. PCT/US2017/040684 § 371(c)(1), (2) Date Dec. 18, 2018, PCT Pub. No. WO2018/013387, PCT Pub. Date Jan. 18, 2018.
Claims priority of provisional application 62/361,562, filed on Jul. 13, 2016.
Prior Publication US 2020/0010368 A1, Jan. 9, 2020
Int. Cl. C04B 35/053 (2006.01); C04B 35/626 (2006.01); C04B 35/645 (2006.01); C23C 14/08 (2006.01); C23C 14/34 (2006.01)

CPC C04B 35/053 (2013.01) [C04B 35/6261 (2013.01); C04B 35/645 (2013.01); C23C 14/081 (2013.01); C23C 14/34 (2013.01); C23C 14/3414 (2013.01); C04B 2235/5409 (2013.01); C04B 2235/5445 (2013.01); C04B 2235/72 (2013.01); C04B 2235/77 (2013.01); C04B 2235/786 (2013.01); C04B 2235/9653 (2013.01)]

12 Claims

1. A method for producing a sintered compact magnesium oxide target for sputtering, the method comprising:

obtaining a raw material by the milling of magnesium oxide (MgO), wherein said raw material include powders comprising magnesium oxide (MgO) having a purity of 99.99 wt % or higher and an average grain size of 0.5 μm or less, said raw material being devoid of MgCO₃; and

hot pressing said milled powder at a temperature of 1700° C. or less and an applied pressure of at least 200 kgf/cm²or more in a uniaxial direction, to obtain a sintered compact magnesium oxide target, thereby said sintered compact magnesium oxide target is not hot isostatic pressed,

wherein said sintered compact magnesium oxide target for sputtering has a density of 3.58 g/cm³or higher;

wherein a variation of a transparency of said target is within 1%.