Methods for forming packaged semiconductor devices including backside power rails and packaged semiconductor devices formed by the same are disclosed. In an embodiment, a device includes a first integrated circuit device including a first transistor structure in a first device layer; a front-side interconnect structure on a front-side of the first device layer; and a backside interconnect structure on a backside of the first device layer, the backside interconnect structure including a first dielectric layer on the backside of the first device layer; and a first contact extending through the first dielectric layer to a source/drain region of the first transistor structure; and a second integrated circuit device including a second transistor structure in a second device layer; and a first interconnect structure on the second device layer, the first interconnect structure being bonded to the front-side interconnect structure by dielectric-to-dielectric and metal-to-metal bonds.

A field-effect transistor includes a substrate, a channel on the substrate including a stem including silicon extending in a vertical direction from the substrate and a number of prongs including silicon extending in a horizontal direction from the stem and spaced apart from each other along the vertical direction, an interfacial layer surrounding the stem and the prongs of the channel, a dielectric layer on the interfacial layer and surrounding the stem and the prongs of the channel, and a metal gate on the dielectric layer and surrounding the stem and the prongs of the channel.

Natural killer (NK) cells are innate lymphocytes with cancer and viral immunosurveillance capabilities. Prior studies have established that human and mouse NK cells can acquire features of adaptive immunity, demonstrating immunological memory-like properties. Memory-like NK cells have been described in response to infection with cytomegalovirus in humans and mice, representing antigen-specific memory NK cells. NK cells, designated as cytokine-induced memory-like NK cells, with adaptive immune cell features can be generated in vitro and used in clinical trials in human cancer patients. Chimeric transmembrane receptor polypeptides expressed in natural killer cells or T-cells, are provided.

Provided are a chimeric antigen receptor, a macrophage expressing same, a method for adjusting macrophage polarization, and the use thereof. The intracellular domain of the chimeric antigen receptor contains an IFN- receptor, and the macrophage expressing the chimeric antigen receptor can maintain an M1 type status for a relatively long time, thereby enhancing the activity of the macrophage M1 type after tumor cell antigens are combined with the chimeric antigen receptor.