Metal grid flexible transparent conductive film and its preparation method and applications
A metal grid flexible transparent conductive film and its preparation method and applications are provided. The conductive film has a flexible substrate and a sputtered metal grid, the metal grid forming various desired patterns on the flexible substrate. Magnetron sputtering method is used to accurately control the thickness of the metal grid layer by controlling the deposition time, so as to prepare a flexible transparent conductive film with good quality, high transmittance, high conductivity and strong bending resistance. The conductive film can be used as a flexible transparent electrode material with excellent properties, and can satisfy the demand of flexible display screen or flexible electronics, and the preparation process is simple, safe and non-toxic, and it can be convenient to prepare a large-area metal grid.
1 . A metal grid flexible transparent conductive film, comprising a flexible substrate and a sputtered metal grid,
wherein the metal grid is disposed on the flexible substrate;
wherein the flexible substrate is selected from a flexible PET substrate, a CPI substrate, and a flexible ultra-thin glass; and
the metal grid is a metal Ag grid,
the metal grid flexible transparent conducive film is prepared by a method comprising:
S1, preparing a polymer template, cutting a desired hollow parallel stripe pattern in the center of the polymer template;
S2, taping a flexible substrate to a substrate to form a flexible substrate/baseboard assembly, and fixing the polymer template prepared in S1 to the flexible substrate to form a template/substrate/baseboard assembly;
S3, placing the template/substrate/baseboard assembly into a magnetron sputtering coating device, passing a rare gas under vacuum conditions, adjusting the power, sputtering a metal target onto the flexible substrate by magnetron sputtering method for deposition, separating the template from the template/substrate/baseboard assembly to obtain the metal grid flexible and transparent conductive film;
wherein:
S1 further comprises adjusting cutting parameters of laser to obtain different polymer template patterns, the cutting parameters comprising cutting energy, cutting spacing and cutting length, the cutting energy is 8-20 W, the cutting spacing is 100-500 μm and the cutting length is 2-20 cm;
S3 further comprises placing the template facing the Ag target under a vacuum of 10 −5 -10 −9 torr, the magnetron sputtering gas Ar bombard the target at a sputtering power of 300-500 W for 90-600 s under a partial pressure of Ar of 60%-70%;
the thickness of metal grid is 150 nm-600 nm;
the line width of the metal grid is 1 μm-10 μm;
the metal grid flexible transparent conductive film has a sheet resistance of 4-1002 sq −1 ;
a light transmittance rate of the metal grid at 550 nm reaches 90% or more; and
an overall transmittance of the metal grid flexible transparent conductive film at 550 nm is more than 82%.
2 . The metal grid flexible transparent conductive film according to claim 1 ,
wherein the metal grid forms a metal square grid, a metal triangular grid, a metal brick wall shaped grid, a metal honeycomb grid, a metal circular grid pattern on the flexible substrate.
3 . The metal grid flexible transparent conductive film according to claim 1 , wherein
the size area of the metal grid ranges from 2 cm×2 cm-20 cm×20 cm.
4 . The metal grid flexible transparent conductive film according to claim 1 , wherein the light transmittance rate of the metal grid at 550 nm is 92% or more.
5 . The metal grid flexible transparent conductive film according to claim 1 , wherein the laser is used S1 to cut a desired hollow parallel stripe pattern in the center of the polymer template.
6 . The metal grid flexible transparent conductive film according to claim 1 , wherein further comprises: cleaning the flexible substrate with acetone and ethanol with a volume ratio of 1:1, and then cleaned in deionized water, blowing dry with nitrogen, and fixing the polymer template on the flexible substrate with high-temperature tape.
7 . The metal grid flexible transparent conductive film according to claim 1 , wherein the polymer template is a polyimide sheet; the overall size of polymer template is 4×4 to 24×24 cm, the thickness is 30 to 90 μm.
8 . The metal grid flexible transparent conductive film according to claim 1 , wherein the metal target is at least one of Ag target, Cu target, Al target, Au target.
9 . Application of the metal grid flexible transparent conductive film of claim 1 in a flexible display or flexible electronic device.
10 . The metal grid flexible transparent conductive film according to claim 1 , wherein the light transmittance rate of the metal grid at 550 nm reaches 93.5% or more.
11 . The metal grid flexible transparent conductive film according to claim 1 , wherein in S3, the deposition time is 90 s-300 s.
12 . The metal grid flexible transparent conductive film according to claim 1 , wherein the pattern of polymer template is a parallel hollow stripe pattern, and the conductive film with a square, triangular or crossed metal grid pattern is obtained by coating 2, 3 or 4 times in S3, respectively.