Method of forming capillary discharge site of plasma display panel using sand blasting

#1. Field of the Invention

#The present invention relates to a plasma display panel, and more particularly, a method of fabricating a capillary discharge site of a plasma display panel using sand blasting. Although the present invention is suitable for a wide scope of applications, it is particularly suitable for forming a capillary discharge site in the capillary discharge plasma display panel by a reliable and inexpensive process.

#2. Discussion of the Related Art

#The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention.

#In the drawings:

#FIG. 1 illustrates a sequence of steps 100 to form one or more capillary discharge sites using sand blasting;

#Reference will now be made in detail to the illustrated embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

#FIG. 1 illustrates the sequence of steps 100 to form one or more capillary discharge sites using sand blasting. The process begins with a set of patterned electrodes and bus structures over a glass substrate 101. The electrodes are then covered with a dielectric layer 102 such as lead oxide (PbO). The PbO layer is then covered with a dry film laminate photoresist 103. The photoresist 103 is then exposed to light 105 through a patterned mask 104 designed to form a desired capillary structure. Such a structure may be, by way of example only, a cylindrical hollow, polygonal or rectangular hollows. After exposure, the film is developed so that the masked pattern 106 appears over the dielectric layer 102. Once the desired pattern is placed on the dielectric layer 102, the surface is sand blasted with fine granular silica or other abrasive materials 107. Since the film material is resistant to the sand blasting, the area over the dielectric layer where the film has been removed is preferentially etched by the impinging particulates. Once the structures are cut to the desired depth, the sand blasting is stopped, and the electrode structure is then treated to remove the remaining photoresist, leaving behind the dielectric layer with the desired capillary discharge sites 108. The electrode structure is then cleaned and prepared for any subsequent processing steps.

#FIG. 2 illustrates a series of microscopic images 200 of actual capillaries formed by the process described by the present invention. In each of the three images, capillaries were cut into an approximately 40 to 45 micron thick layer of PbO 210 at a depth of approximately 30 microns, leaving approximately 10 to 15 microns of PbO at the bottom of the capillaries. The first image illustrates capillaries of 75-micron diameter 205. The second image illustrates capillaries of 100-micron diameter 215. And, the third image illustrates capillaries of 125-micron diameter 220.