The present disclosure relates to semiconductor structures and, more particularly, to a substrate with trap rich and low resistivity regions and methods of manufacture. The structure includes: a high resistivity semiconductor substrate; an active device over the high resistivity semiconductor substrate; and a low resistivity region floating in the high resistivity semiconductor substrate and which is below the active device.

In semiconductor devices, high-k dielectric materials may be formed on the basis of engineered surface conditions, thereby contributing to superior uniformity of the resulting characteristics. In some illustrative embodiments, the dielectric material may be stabilized in a ferroelectric phase, wherein the previous surface modulation, which, in the illustrative embodiments may include the introduction of respective species, such as dopant species, thereby contributing to uniform ferroelectric characteristics. In some illustrative embodiments, the process strategy may be applied to a buried insulating layer of an SOI substrate.

Structures with altered crystallinity beneath semiconductor devices and methods associated with forming such structures. Trench isolation regions surround an active device region composed of a single-crystal semiconductor material. A non-single-crystal layer has a first section arranged beneath the trench isolation regions and a second section arranged beneath the active device region. The first section of the non-single-crystal layer has a first width in a vertical direction. The second section of the non-single-crystal layer has a second width in the vertical direction that is less than the first width of the first section of the non-single-crystal layer.

Methods of increasing the optical path length and bandwidth of a Ge-based photodiode while reducing the diode area and capacitance without compromising the optical responsivity and the resulting devices are provided. Embodiments include providing a Si substrate having a BOX layer over the Si substrate and a Si layer over the BOX layer; forming an oxide layer over the Si layer; forming a trench in the oxide layer, the trench having a center strip and a plurality of opposing fins; epitaxially growing Ge in the trench and above the oxide layer; and removing the oxide layer, a Ge center strip and a plurality of opposing fins remaining.

In accordance with an embodiment, a method for producing a buried cavity structure includes providing a mono-crystalline semiconductor substrate, producing a doped volume region in the mono-crystalline semiconductor substrate, wherein the doped volume region has an increased etching rate for a first etchant by comparison with an adjoining, undoped or more lightly doped material of the monocrystalline semiconductor substrate, forming an access opening to the doped volume region, and removing the doped semiconductor material in the doped volume region using the first etchant through the access opening to obtain the buried cavity structure.

A semiconductor device and a fabricating method of the same are provided. The semiconductor device a substrate including an active region defined by an element isolation film, an impurity region having a first conductivity type in the active region, a first semiconductor film of a second conductivity type on the impurity region, a buried insulating film on the first semiconductor film, a second semiconductor film on the buried insulating film, and a well contact connected to the first semiconductor film. The level of a lowermost surface of the first semiconductor film is higher than a level of a lowermost surface of the element isolation film.

An isolation structure formed in a semiconductor substrate of a first conductivity type includes a region of a second conductivity type opposite to the first conductivity type. The region of the second conductivity type is saucer-shaped and has a floor portion substantially parallel to the top surface of the substrate and a sloped sidewall portion. The sloped sidewall portion extends downward from the top surface of the substrate at an oblique angle and merges with the floor portion. The floor portion and the sloped sidewall portion together form an isolated pocket of the substrate.

In accordance with an embodiment of an integrated circuit, a cavity is buried in a semiconductor body below a first surface of the semiconductor body. An active area portion of the semiconductor body is arranged between the first surface and the cavity. The integrated circuit further includes a trench isolation structure configured to provide a lateral electric isolation of the active area portion.

An isolation structure formed in a semiconductor substrate of a first conductivity type includes a floor isolation region of a second conductivity type opposite to the first conductivity type submerged in the substrate. A first trench extends downward from a surface of the substrate and overlaps onto the floor isolation region. The first trench includes walls lined with a dielectric material and contains a conductive material. The first trench and the floor isolation region electrically isolate a pocket of the first conductivity type from the substrate.

A method for fabricating a semiconductor device includes forming an opening in a first epitaxial lateral overgrowth region to expose a surface of the semiconductor substrate within the opening. The method further includes forming an insulation region at the exposed surface of the semiconductor substrate within the opening and filling the opening with a second semiconductor material to form a second epitaxial lateral overgrowth region using a lateral epitaxial growth process.