Semiconductor seed layer

As a result, nearly perfect interfaces between the ferromagnetic material and the semiconductor are not a prerequisite for efficient spin injection. It is for example possible to insert a non-magnetic seed layer between the ferromagnetic base layer and the semiconductor collector. Since hot electrons retain their spin moment while traversing the thin non-magnetic layer this will not drastically reduce the spin polarization of the injected current. Finally, since electron injection is ballistic in SVT and MTT devices the spin injection efficiency is not fundamentally limited by a substantial conductivity mismatch between metals and semiconductors [161, 162], The latter is the case in diffusive ferromagnetic metal/semiconductor contacts [163],... 

Electroless copper seed layer on TaN surfaces for Cu metallization in the back-end-of-line semiconductor fabrication was also investigated.38 After etching in diluted HF solution and activation with PdCb, the electroless deposition of copper (to be used as a seed layer) was carried out from CuSCVEDTA solution containing Triton X-100, tetramethyl ammonium hydroxide (TMAH), and formaldehyde as a reducing agent of Cu(II) ions. 

Recently, copper plating has found an important new application in metallizing interconnects on semiconductor wafers3. Here, a specially designed and dedicated tool is used to plate well-defined disk-shaped silicon wafers. A very uniform copper layer must be electrodeposited with excellent gap-fill properties onto a resistive seed layer through contacts along the circumference of the wafer. The new process poses numerous critical challenges ... 

Copper is going to replace aluminum as the material of choice for semiconductor interconnects due to its low electrical resistance and high electromigration resistance (1-4). An inlaid interconnect is used for copper metallization in which the insulating dielectric material is deposited first, trenches and vias are formed by patterning and selective dielectric etching, and then diffusion barrier and copper seed layer are deposited into the trenches and vias (5). 

The ECD seed layer process is useful in extending the inlaid copper metallization process beyond the limit of PVD seed layers. This process will allow the semiconductor industry to use current low cost copper deposition processes, even as device geometries continues to shrink. 

Applications in Semiconductor Technology 1141 Barrier (Ta) Cu seed layer. 

Orthorhombic black phosphorus was originally produced by the action of high pressure on the white or red form [36], It was later made by the action of heat on white mixed with mercury and in the presence of a seed crystal of black. This form of the element has a continuous double-layer structure in which each P atom forms three bonds of length 2.23 A, pyramidally disposed at mutual angles of lOO (Figure 4.3). It is a semiconductor and exhibits flakiness similar to mica and graphite layer structures. ... 

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