Abstract: A method includes depositing a first work-function layer and a second work-function layer in a first device region and a second device region, respectively, and depositing a first fluorine-blocking layer and a second fluorine-blocking layer in the first device region and the second device region, respectively. The first fluorine-blocking layer is over the first work-function layer, and the second fluorine-blocking layer is over the second work-function layer. The method further includes removing the second fluorine-blocking layer, and forming a first metal-filling layer over the first fluorine-blocking layer, and a second metal-filling layer over the second work-function layer.

Abstract: Semiconductor device structures having gate structures with tunable threshold voltages are provided. Various geometries of device structure can be varied to tune the threshold voltages. In some examples, distances from tops of fins to tops of gate structures can be varied to tune threshold voltages. In some examples, distances from outermost sidewalls of gate structures to respective nearest sidewalls of nearest fins to the respective outermost sidewalls (which respective gate structure overlies the nearest fin) can be varied to tune threshold voltages.

Abstract: A device includes a semiconductor fin, and a gate stack on sidewalls and a top surface of the semiconductor fin. The gate stack includes a high-k dielectric layer, a work-function layer overlapping a bottom portion of the high-k dielectric layer, and a blocking layer overlapping a second bottom portion of the work-function layer. A low-resistance metal layer overlaps and contacts the work-function layer and the blocking layer. The low-resistance metal layer has a resistivity value lower than second resistivity values of both of the work-function layer and the blocking layer. A gate spacer contacts a sidewall of the gate stack.

Abstract: An absorption refrigeration system uses a solution and a refrigerant contained in the solution as working mediums.