US 12,439,513 B2
Use of inorganic thin non-woven dielectrics in printed circuit boards
Tarun Amla, San Jose, CA (US); Keshav Amla, San Jose, CA (US); and Jyoti Amla, San Jose, CA (US)
Assigned to ADVANCED CHIP AND CIRCUIT MATERIALS, INC., San Jose, CA (US)
Filed by AVISHTECH, INC., San Jose, CA (US)
Filed on Apr. 4, 2023, as Appl. No. 18/130,768.
Prior Publication US 2024/0341032 A1, Oct. 10, 2024
Int. Cl. H05K 1/03 (2006.01)
CPC H05K 1/0366 (2013.01) [H05K 2201/0293 (2013.01); H05K 2201/068 (2013.01)] 14 Claims
 
1. A printed circuit board, comprising:
at least one dielectric material layer comprising a non-woven, inorganic fabric reinforcement impregnated with a crosslinked thermosetting polymer resin, the crosslinked thermosetting polymer resin having a density of less than about 1.6 g/cc and a dissipation factor (DF) of less than about 0.010,
wherein the at least one dielectric material layer has a thickness of less than about 125 microns upon lamination and is characterized by:
a thickness reduction of at least 25% relative to a thickness of the non-woven, inorganic fabric reinforcement prior to lamination;
a glass transition temperature (Tg) of greater than about 150° C.;
a coefficient of thermal expansion (CTE) of less than about 35 ppm in either of the planar directions over a temperature range of about 50° C. to about 220° C.; and
a dielectric constant (DK) of less than about 3.5.