Publisher Summary The chapter discusses various deposition processes, such as sputter deposition, arc vapor deposition, and chemical vapor deposition (CVD). Directed deposition is confining the vapor flux to one axis by eliminating off-axis components of the flux. Directed deposition can be attained by collimation of the vaporized material. In sputtering, this can be done using a honeycomb structure between the source and the substrate. Thermal evaporation is the vaporization of a material by heating to a temperature, such that the vapor pressure becomes appreciable and atoms or molecules are lost from the surface in a vacuum. Discussion of arcs and arc vapor deposition is somewhat difficult because of the varying definitions of an arc. These definitions vary from a low-voltage, high-current discharge among electrodes to a discharge in a gas or vapor that has a voltage drop at the cathode of the order of the minimum ionizing or minimum exciting potential of the gas or vapor to a self-sustained discharge capable of supporting large currents by providing its own mechanism of electron emission from the negative electrode. CVD began to be developed with the purpose of strengthening carbon filaments in the first light bulbs.