US 11,916,034 B2
Semiconductor chip and semiconductor device including a copper pillar and an intermediate layer and a concave portion formed at one end surface of the copper pillar
Shoji Takei, Kyoto (JP); and Yuji Koga, Kyoto (JP)
Assigned to ROHM CO., LTD., Kyoto (JP)
Filed by ROHM CO., LTD., Kyoto (JP)
Filed on Jul. 8, 2022, as Appl. No. 17/860,291.
Application 17/860,291 is a continuation of application No. 16/832,946, filed on Mar. 27, 2020, granted, now 11,417,623.
Claims priority of application No. 2019-068474 (JP), filed on Mar. 29, 2019.
Prior Publication US 2022/0344299 A1, Oct. 27, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. H01L 23/31 (2006.01); H01L 23/532 (2006.01); H01L 23/00 (2006.01)
CPC H01L 24/29 (2013.01) [H01L 23/3114 (2013.01); H01L 23/53228 (2013.01); H01L 2224/29155 (2013.01); H01L 2924/18161 (2013.01)] 25 Claims
OG exemplary drawing
 
1. A semiconductor chip comprising:
a semiconductor layer having a first surface;
a first insulating layer formed at the first surface of the semiconductor layer;
a conductive layer formed on the first insulating layer, the conductive layer made of a metal mainly containing Cu;
a second insulating layer formed on the first insulating layer, the second insulating layer covering the conductive layer, the second insulating layer having an opening from which a part of the conductive layer is exposed;
a Copper pillar extending in a thickness direction such that the Copper pillar is formed over the second insulating layer and the conductive layer, the Copper pillar made of a metal mainly containing Cu and electrically connected to the conductive layer through the opening;
an intermediate layer formed between the conductive layer and the Copper pillar, the intermediate layer made of a material having a linear expansion coefficient smaller than a linear expansion coefficient of the conductive layer and smaller than a linear expansion coefficient of the Copper pillar; and
a concave portion formed at one end surface of the Copper pillar, wherein the concave portion has a bottom surface opposed to the opening in the thickness direction and a side surface which extends upwardly in a convex arc shape from the bottom surface in a cross section, and wherein
an acute angle between a tangent line of a surface of the convex arc shape and a surface of the concave portion becomes steeper as the tangent line becomes closer to a side edge of the Copper pillar in a cross section.