US 12,249,974 B2
Crystal oscillator and method of making the same
Ray-Hua Horng, Taichung (TW); and Yi-Lun Lin, Taichung (TW)
Assigned to AKER TECHNOLOGY CO., LTD., Taichung (TW)
Filed by AKER TECHNOLOGY CO., LTD., Taichung (TW)
Filed on Apr. 25, 2023, as Appl. No. 18/306,619.
Claims priority of application No. 111120274 (TW), filed on May 31, 2022.
Prior Publication US 2023/0387884 A1, Nov. 30, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H03H 9/19 (2006.01); H03H 3/02 (2006.01); H03H 9/13 (2006.01)
CPC H03H 9/19 (2013.01) [H03H 3/02 (2013.01); H03H 9/132 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A crystal oscillator, comprising:
a piezoelectric substrate including a thinned portion, two side portions extending upwardly from two opposite ends of said thinned portion, and a cavity defined by said thinned portion and said two side portions, said thinned portion having an upper surface and a lower surface opposite to each other and respectively defining an upper surface work portion and a lower surface work portion that are spaced apart from a plurality of ends of said thinned portion, said upper surface of said thinned portion facing said cavity, at least one of said two side portions having a recessed portion extending inwardly from a top surface thereof and communicating with said cavity, wherein said upper surface of said thinned portion and a bottom surface of said recessed portion are flush with each other;
a top electrode layer disposed on said upper surface of said thinned portion and having a top work portion disposed on said upper surface work portion of said thinned portion, and a top extension extending from said top work portion onto said bottom surface of said recessed portion; and
a bottom electrode layer disposed on said lower surface of said thinned portion and having a bottom work portion disposed on said lower surface work portion of said thinned portion, and a bottom extension extending from said bottom work portion toward said one end of said thinned portion and then bending upward and inward onto said bottom surface of said recessed portion.