Electrowetting device with spacer and preparation method of electrowetting device

Abstract

The invention discloses an electrowetting device with a spacer and a preparation method of the electrowetting device. The method comprises the steps of firstly taking a space material, carrying out thermocuring under yellow light and grinding to obtain spacer microspheres; spraying the spacer microspheres on a coated pixel wall material, curing the pixel wall material, and carrying out once photoetching to prepare a pixel wall and a spacer at the same time; and removing the spacer microspheres sprayed in an un-photoetched curing area in the developing process and only leaving partial structure of the microspheres in a photoetched curing area. When an upper substrate and / or lower substrate deforms, the spacer is in contact with the upper substrate and inter collapse of the electrowetting device can be effectively prevented. The spacer is obtained through photoetching the microspheres, so that the spacer does not affect the connectivity of a polar electrolyte solution; the pixel wall and the spacer are obtained through one-step photoetching, so that an error chain caused by twice photoetching alignment is avoided in comparison with the spacer prepared through twice photoetching, and the electrowetting device is higher in precision, simpler in process and lower in operation difficulty.

Description

Technical field [0001] The invention relates to the technical field of electrowetting, in particular to an electrowetting device with spacers and a preparation method thereof. Background technique [0002] The so-called wetting refers to the process in which one fluid on the solid surface is replaced by another fluid. The liquid can spread on the solid surface, and the solid-liquid contact surface has a tendency to expand, that is, the adhesion of the liquid to the solid surface is greater than its cohesion, which is wetting. The liquid cannot spread on the solid surface, and the contact surface has a tendency to shrink into a spherical shape, that is, non-wetting, which means that the adhesion of the liquid to the solid surface is less than its cohesion. Electrowetting (EW) refers to the phenomenon of changing the wettability of the droplet on the substrate by changing the voltage between the droplet and the insulating substrate, that is, changing the contact angle to cause the...

AI Technical Summary

Problems solved by technology

This method of preparing spacers by UV curing can also be applied to electrowetting display devices in theory, but there are risks in the actual operation process, such as: UV photopolymerization materials or photoinitiators can be mixed with non-polar The solution 5' dissolves or extracts the colored solute in the non-polar solution 5'; the ultraviolet photopolymerization material or photoinitiator reacts insufficiently during the polymerization process, and there are residual substances in the polar electrolyte solution 4' that affect its conductivity and polarity The wettability of the electrolyte solution 4' on the hydrophobic insulating layer 7' in the electrified state; a mask is needed to define the position of the polymer during the polymerization process, the alignment accuracy of the mask and the thickness and upper surface of the mask The thickness of the support plate 1 and the refraction of ultraviolet light will produce deviations in the actual position of the polymer formation, thereby forming contact with the non-polar solution 5'

In addition, the patent mentions that the support column is prepared at the intersection of the pixel wall by secondary photolithography to solve the problem of device center collapse. The preparation process requires high alignment accuracy for lithography equipment. At the same time, due to the need for two alignments, the preparation process is more complicated, and the superposition of the first and second alignment errors will easily cause the position of the support column to shift from the pixel wall. The cross cross will cause the function of this method to fail, and will bring other problems such as affecting the filling of the colored non-polar solution and the display effect of the device.

[0005] At present, electrowetting display devices can partially solve the problem of device center collapse by increasing the thickness of the sealant. The thickness of the sealant needs to be much larger than the deformation of the upper and lower substrates. However, this method is suitable for large-size display panels and ultra-thin glass as The upper and lower substrate electrowetting devices still have the problem of collapse

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