摘要 |
Semiconductor devices having enhanced mobility regions and methods of forming such devices are disclosed. In some embodiments, a method includes providing a SiGe layer on a supporting substrate, and forming isolation structures within the SiGe layer that define a first region and a second region. The conductivity of the SiGe layer in the second region may be altered to form a suitably doped well. A layer of strained Ge can be formed on the well, and a layer of strained Si may be formed on the surface of the first region. A layer of strained Si may be formed on the strained Ge layer. Source/drain regions may be formed in the well and in the first device region, and a dielectric layer may be formed on the Si layer. Gate structures may then be positioned on the dielectric layer.
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