and base plate of the display device the substrate is formulated to be light weight insulative and with a high compressive strength for resisting atmospheric loads placed on the display screen by the reduced pressure in addition the substrate is formulated to be easily etched laser ablated or photochemically machined and assembled as a third member spacer structure application_number US 61892896 A description initially a substrate is formed of an aerogel xerogel or photosensitive material e g photosensitive glass photosensitive aerogel photosensitive xerogel a substrate comprising an aerogel or xerogel material can be formed as a sheet and then patterned and etched using dry etching or laser ablation processes this is shown in fig1 4 a substrate comprising a photosensitive material can be patterned and etched using a photochemical machining process this is shown in fig5 a 5d fig6 shows a substrate constructed in accordance with the invention assembled as used as a spacer in an assembled fed with reference to fig1 a substrate 10 is formed of a sheet of aerogel or xerogel material having a predetermined thickness of 34 t 34 by way of example the thickness 34 t 34 may be on the order of 10 u03bcm to 1000 u03bcm in addition the substrate 10 is formed with a polygonal peripheral configuration having predetermined length 34 l 34 and width 34 w 34.