Abstract:
An epitaxially grown channel layer is provided on a well structure after ion implantation steps and heat treatment steps are performed to establish a required dopant profile in the well structure. The channel layer may be undoped or slightly doped, as required, so that the finally obtained dopant concentration in the channel layer is significantly reduced compared to a conventional device to thereby provide a retrograde dopant profile in a channel region of a field effect transistor. Additionally, a barrier diffusion layer may be provided between the well structure and the channel layer to reduce up-diffusion during any heat treatments carried out after the formation of the channel layer. The final dopant profile in the channel region may be adjusted by the thickness of the channel layer, the thickness and the composition of the diffusion barrier layer and any additional implantation steps to introduce dopant atoms in the channel layer.
Abstract:
A method is disclosed which includes implanting an inert species in a layer of a gate electrode material (205A), the gate electrode material being formed above a substrate (201) and having a P-doped layer portion and an N-doped layer portion, forming a first gate electrode (205P) from the P-doped layer portion and a second gate electrode (205N) from the N-doped layer portion, performing a wet chemical cleaning process, and forming a first transistor (200B) on the basis of the first gate electrode (205P) and a second transistor (200A) on the basis of the second gate electrode (205N).
Abstract:
High-k dielectric spacer elements on the gate electrode of a field effects transistor in combination with an extension region that is formed by dopant diffusion from the high-k spacer elements into the underlying semiconductor region provides for an increased charge carrier density in the extension region. In this way, the limitation of the charge carrier density to approximately the solid solubility of dopants in the extension region may be overcome, thereby allowing extremely shallow extension regions without unduly compromising the transistor performance.
Abstract:
A field effect transistor 300 comprises a gate insulation layer including an anisotropic dielectric 305. The orientation is selected such that a first permittivity parallel to the gate insulation layer is significantly less than a second permittivity perpendicular to the gate insulation layer.
Abstract:
An SOI transistor element and a method of fabricating the same is disclosed, wherein a high concentration of stationary point defects is created by including a region within the active transistor area that has a slight lattice mismatch. In one particular embodiment, a silicon germanium layer 320 is provided in the active area having a high concentration of point defects due to relaxing the strain of the silicon germanium layer upon heat treating the transistor element. Due to the point defects, the recombination rate is significantly increased, thereby reducing the number of charged carriers stored in the active area.
Abstract:
A method is disclosed in which different metal layers (240, 242) are sequentially deposited on silicon-containing regions so that the type and thickness of the metal layers (240, 242) may be adapted to specific characteristics of the underlying silicon-containing regions. Subsequently, a heat treatment is performed to convert the metals into metal silicides so as to improve the electrical conductivity of the silicon-containing regions. In this way, silicide portions (241, 243) may be formed that are individually adapted to specific silicon-containing regions so that device performance of individual semiconductor elements or the overall performance of a plurality of semiconductor elements may significantly be improved. Moreover, a semiconductor device is disclosed comprising at least two silicon-containing regions having formed therein differing silicide portions (241, 243), wherein at least one silicide portion comprises noble metal.
Abstract:
In a method for fabricating a semiconductor device different types of a metal-semiconductor compound (241, 261) are formed on or in at least two different conductive semiconductor regions so that for each semiconductor region the metal-semiconductor compound region may be formed to obtain an optimum overall performance of the semiconductor device. On one of the two semiconductor regions, the metal-semiconductor compound is formed of at least two different metal layers (240, 260), whereas the metal-semiconductor compound in or on the other semiconductor region is formed from a single metal layer (240).
Abstract:
By providing a test structure (100) including a plurality of test pads (104), the anisotropic behavior of stress and strain influenced electrical characteristics, such as the electron mobility, may be determined in a highly efficient manner. Moreover, the test pads (104) may enable the detection of stress and strain induced modifications with a spatial resolution in the order of magnitude of individual circuit elements.
Abstract:
By forming an implantation mask (220) prior to the definition of the drain and the source areas (208), an effective decoupling of the gate dopant concentration from that of the drain and source concentrations is achieved. Moreover, after removal of the implantation mask (220), the lateral dimension of the gate electrode (205) may be defined by well-established sidewall spacer (207) techniques, thereby providing a scaling advantage with respect to conventional approaches based on photolithography and anisotropic etching.
Abstract:
In highly sophisticated MOS transistors including nickel silicide portions (311) for reducing the silicon sheet resistance, nickel silicide stingers may lead to short circuits between the drain and source region and the channel region, thereby significantly lowering production yield. By substantially amorphizing corresponding portions (331) of the source and drain regions, the creation of clustered point defects may effectively be avoided during curing implantation induced damage, wherein a main diffusion path for nickel during the nickel silicide formation is interrupted. Thus, nickel silicide stingers may be significantly reduced or even completely avoided.