An electrowetting device with a spacer and its preparation method

Abstract

The invention discloses an electrowetting device with a spacer and a preparation method thereof. The spacer material is firstly taken, heat-cured under yellow light, and ground to obtain spacer microspheres, and then the spacer microspheres are sprinkled on the coated On the pixel wall material, the pixel wall material is cured again, and then the pixel wall and the spacer are prepared at the same time by one photolithography. The partial structure of the microspheres in the curing area, when the upper substrate and / or the lower substrate are deformed, the spacer is in contact with the upper substrate, which can effectively prevent the internal collapse of the electrowetting device; because the spacer The spacer is obtained by photolithography of microspheres, and the spacer will not affect the connectivity of the polar electrolyte solution; because the pixel wall and the spacer are obtained by one-step photolithography, compared with the preparation of the spacer by two photolithography There is no error chain caused by two lithography alignments, the precision is higher, the process is simpler, and the operation is less difficult.

Description

technical field [0001] The invention relates to the field of electrowetting technology, in particular to an electrowetting device with a spacer and a preparation method thereof. Background technique [0002] The so-called wetting refers to the process in which one fluid on a solid surface is replaced by another fluid. The liquid can spread on the solid surface, and the solid-liquid contact surface tends to expand, that is, the adhesion force of the liquid to the solid surface is greater than its cohesive force, which is wetting. The liquid cannot spread on the solid surface, and the contact surface tends to shrink into a spherical shape, that is, it is not wet, and the non-wet means that the adhesion force of the liquid to the solid surface is less than its cohesive force. Electrowetting (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, ...

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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