Effect of Low-Pressure Plasma Treatment Parameters on Wrinkle Features

Abstract

Wrinkles attract significant attention due to their ability to enhance the mechanical and optical characteristics of various optoelectronic devices. We report the effect of the plasma gas type, power, flow rate, and treatment time on the wrinkle features. When an optical adhesive was treated using a low-pressure plasma of oxygen, argon, and nitrogen, the oxygen and argon plasma generated wrinkles with the lowest and highest wavelengths, respectively. The increase in the power of the nitrogen and oxygen plasma increased the wavelengths and heights of the wrinkles; however, the increase in the power of the argon plasma increased the wavelengths and decreased the heights of the wrinkles. Argon molecules are heavier and smaller than nitrogen and oxygen molecules that have similar weights and sizes; moreover, the argon plasma comprises positive ions while the oxygen and nitrogen plasma comprise negative ions. This resulted in differences in the wrinkle features. It was concluded that a combination of different plasma gases could achieve exclusive control over either the wavelength or the height and allow a thorough analysis of the correlation between the wrinkle features and the characteristics of the electronic devices.

Barrier Diamond-like Carbon Coatings on Polydimethylsiloxane Substrate

“…Among all modifications, the lowest values of the obtained wavelength were observed for processes conducted with the use of oxygen plasma. Interestingly, similar results were reported by Gu et al [ 45 ], although they conducted the modifications at low power ranges of up to 60 W. The highest wavelength values were characteristic of the argon atmosphere, which, as indicated in the literature [ 45 ], is related to the greater penetration depth of argon molecules due to their smaller size and greater weight than molecules formed, e.g., in nitrogen or oxygen plasma, as well as positive charge (opposite to the negative charge of oxygen or nitrogen ions). By analyzing the obtained values of parameters, namely λ, A, Ra, and Rz, it can be seen that the latter are closely related to the obtained amplitude values.…”

“…The presented results prove that the change in the negative self-bias potential influences changes in the surface geometry of the modified PDMS substrates. This effect is also known from the literature [ 11 , 45 , 46 ]. As other papers indicate [ 14 , 46 , 47 ], wrinkles formed on polymers may have a hierarchical character (i.e., two separate profile runs related to the modification in the micro and nanoscale can be distinguished).…”

Flexible Transparent Electrodes Formed from Template‐Patterned Thin‐Film Silver

“…Figure 2c,d shows equivalent AFM images for e-OA on glass.Oxygen plasma treatment of the bare OA film led to a substantial increase in the surface roughness to 11.8 nm (Figure2c), with the observed morphology resembling a series of separate but closely spaced vertical pillars of typical width 60 -90 nm. The observed increase in the surface roughness of the NOA63 is consistent with a previous report, in which partially cured NOA63 on a rigid acrylic substrate underwent wrinkling when subjected to (low pressure) oxygen plasma treatment as a result of stress induced by the colliding oxygen ions [31]. The same pillared structure was broadly maintained after depositing 12 nm of silver, albeit with a reduction in ℜ to ≈7.5 nm.…”

“…The observed increase in the surface roughness of the NOA63 is consistent with a previous report, in which partially cured NOA63 on a rigid acrylic substrate underwent wrinkling when subjected to (low pressure) oxygen plasma treatment as a result of stress induced by the colliding oxygen ions. [ 31 ] The same pillared structure was broadly maintained after depositing 12 nm of silver, albeit with a reduction in ℜ to ≈7.5 nm. As we show below, the spatial separation of the silver‐coated e‐OA pillars leads to extremely poor in‐plane conductivity, with the fragmented silver effectively behaving as an insulator over macroscopic length scales.…”

Special Issue: Processing, Structure, Dynamics and Mechanical Properties of Polymeric Materials

“…They proved that by changing the original composition formulation, it is possible to change the structure and thus the properties of the copolymers in the desired direction. A wavy physical structure with a periodicity that can impart flexibility to optoelectronic devices and control the optical path through a material stack has been affected by a low-pressure plasma of oxygen, argon, and nitrogen, as well as the power, flow rate and treatment time, as it was observed by Gu et al [6].…”