US 9,810,635 B2
Method of accurate thickness measurement of boron carbide coating on copper foil
Jeffrey L. Lacy, Houston, TX (US); and Murari Regmi, Houston, TX (US)
Assigned to Proportional Technologies, Inc., Houston, TX (US)
Filed by Proportional Technologies, Inc., Houston, TX (US)
Filed on Nov. 12, 2015, as Appl. No. 14/938,903.
Claims priority of provisional application 62/078,674, filed on Nov. 12, 2014.
Prior Publication US 2016/0161416 A1, Jun. 9, 2016
Int. Cl. G01N 21/00 (2006.01); G01N 21/73 (2006.01); G01N 21/68 (2006.01); G01N 21/84 (2006.01)
CPC G01N 21/73 (2013.01) [G01N 21/68 (2013.01); G01N 2021/8427 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A process for measuring the effective thickness of a boron coating on copper foil comprising the steps of:
(1) removing a sample of the boron coated copper foil from a larger length coated substrate;
(2) weighing the sample of boron coated copper foil;
(3) contacting the sample of boron coated copper foil with an etching solution;
(4) allowing the etching solution to dissolve the sample of boron coated copper foil;
(5) diluting the etching solution;
(6) determining the concentration of the material in the diluted etching solution utilizing inductively coupled plasma optical emission spectroscopy; and
(7) calculating the effective thickness of the coating (ts) using the equation:
ts=[(1.3C×Vs×df×tcu×dcu/Mt)×1/(1−1.3C×Vs×df/Mt)]
where C=measured concentration from determining step
df=sample dilution factor
Vs=volume of diluted etching solution
tcu=thickness of the copper foil
dcu—density of the copper foil
Mt=mass of the boron coated sample.