US 12,230,541 B2
Element chip manufacturing method
Atsushi Harikai, Osaka (JP); Shogo Okita, Hyogo (JP); Akihiro Itou, Kyoto (JP); and Toshiyuki Takasaki, Osaka (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
Filed on Nov. 30, 2021, as Appl. No. 17/456,914.
Claims priority of application No. 2020-201996 (JP), filed on Dec. 4, 2020.
Prior Publication US 2022/0181209 A1, Jun. 9, 2022
Int. Cl. H01L 21/78 (2006.01); H01L 21/304 (2006.01); H01L 21/3065 (2006.01)
CPC H01L 21/78 (2013.01) [H01L 21/304 (2013.01); H01L 21/3065 (2013.01)] 4 Claims
OG exemplary drawing
 
1. An element chip manufacturing method comprising:
a preparing process of preparing a substrate including a plurality of element regions and a dividing region that defines the element regions, the substrate having a first principal surface and a second principal surface located opposite to the first principal surface, the substrate including a semiconductor layer;
a groove forming process of forming a groove in the dividing region from the first principal surface side of the substrate, the groove being formed halfway in a thickness direction of the semiconductor layer; and
a grinding process of grinding the substrate from the second principal surface side, to divide the substrate into a plurality of element chips,
wherein the groove formed in the groove forming process includes a first region constituted by a side surface having a first surface roughness, and a second region constituted by a side surface having a second surface roughness larger than the first surface roughness in the semiconductor layer,
wherein the groove forming process includes:
a first plasma processing process of trenching the substrate by continuously etching the substrate, to form the first region having no scallop; and
a second plasma processing process of trenching the substrate by repeating an etching step of etching the substrate, a depositing step of depositing a protection film, and a protection film removing step of removing at least a portion of the protection film, to form the second region having scallops and,
in the grinding process, grinding of the substrate is performed until reaching the first region of the groove.