Abstract: A semiconductor device is provided with a first layer having a first layer conductive contact and being doped at a first concentration of a first dopant type. The first dopant type being a P type dopant. A second layer is on top the first layer and being doped at a second concentration of the first dopant type. The second concentration being less than the first concentration. A third layer is on top of the second layer and having a third layer conductive contact and being doped with a second dopant type, the second dopant type being an N type dopant. A fourth layer is on top of the third layer and having a fourth layer conductive contact and being doped with the first dopant type, wherein at least one of the first and second layers is a boron arsenide (BAs) layer.

Abstract: A semiconductor photodiode which functions in a wide band range up to medium wave infrared and far wavelengths in addition to visible region and near infrared includes: a light absorber region in micro structure which can provide light absorbance upon being roughened by laser; a first electrical lower contact coated with metal materials such as aluminium (Al), silver (Ag); a silicon which consists of crystalline silicon (c-Si); a second electrical lower contact which is coated with metal materials such as aluminium (Al), silver (Ag); a chalcogen doped hyper-filled silicone region which is obtained as a result of doping by pulse laser to the silicone region implanted by chalcogen elements; and upper electrical contact parts which are coated generally in the thickness range of 10 nm-1000 nm by using two-layered alloys with aluminium (Al)—(Al)-silver (Ag), two-layered alloys with titanium (Ti)-gold (Au), three-layered alloys with Ti-Platinum(Pt)—Au—Ag or three-layered alloys with Ti-lead(Pb)—Ag.

Abstract: A semiconductor on insulator multilayer structure is provided. The multilayer comprises a high resistivity single crystal semiconductor handle substrate, an optionally relaxed semiconductor layer comprising silicon, germanium, or silicon germanium, an optional polycrystalline silicon layer, a dielectric layer, and a single crystal semiconductor device layer.

Abstract: The present disclosure provides methods of fabricating a semiconductor device. A method according to one embodiment includes forming, on a substrate, a first fin formed of a first semiconductor material and a second fin formed of a second semiconductor material different from the first semiconductor material, forming a semiconductor cap layer over the first fin and the second fin, and annealing the semiconductor cap layer at a first temperature while at least a portion of the semiconductor cap layer is exposed.

Abstract: A semiconductor or other substrate can include one or more electrodes, located directly or indirectly on the substrate, separated from each other and coupled to the substrate. At the two or more electrodes, non-zero frequency time-varying electrical energy can be received. The time-varying electrical energy can be coupled via the two or more electrodes to trigger a displacement current to activate free carriers confined within the semiconductor substrate to generate frequency-controlled heat in the semiconductor substrate.

Abstract: An apparatus and method of processing a workpiece is disclosed, where a sacrificial capping layer is created on a top surface of a workpiece. That workpiece is then exposed to an ion implantation process, where select species are used to passivate the workpiece. While the implant process is ongoing, radicals and excited species etch the sacrificial capping layer. This reduces the amount of etching that the workpiece experiences. In certain embodiments, the thickness of the sacrificial capping layer is selected based on the total time used for the implant process and the etch rate. The total time used for the implant process may be a function of desired dose, bias voltage, plasma power and other parameters. In some embodiments, the sacrificial capping layer is applied prior to the implant process. In other embodiments, material is added to the sacrificial capping layer during the implant process.

Abstract: A semiconductor on insulator multilayer structure is provided. The multilayer comprises a high resistivity single crystal semiconductor handle substrate, an optionally relaxed semiconductor layer comprising silicon, germanium, or silicon germanium, an optional polycrystalline silicon layer, a dielectric layer, and a single crystal semiconductor device layer.

Abstract: A silicon carbide semiconductor substrate includes a silicon carbide substrate of a first conductivity type, an epitaxial layer of the first conductivity type provided on a front surface of the silicon carbide substrate, an impurity concentration of the epitaxial layer being 1×1017/cm3 to 1×1018/cm3, and a film thickness of the epitaxial layer being 1 ?m to 5 ?m. The silicon carbide semiconductor substrate further includes a buffer layer of the first conductivity type provided on a surface of a first side of the epitaxial layer opposite a second side facing the silicon carbide substrate, an impurity concentration of the buffer layer being about a same as that of the silicon carbide substrate, and a drift layer of the first conductivity type provided on a surface of a first side of the buffer layer opposite a second side facing toward the silicon carbide substrate, an impurity concentration of the drift layer being lower than that of the buffer layer.

Abstract: A method of fabrication of a semiconductor element includes a step of rapid heat treatment in which a substrate comprising a base having a resistivity greater than 1000 Ohm·cm is exposed to a peak temperature sufficient to deteriorate the resistivity of the base. The step of rapid heat treatment is followed by a curing heat treatment in which the substrate is exposed to a curing temperature between 800° C. and 1250° C. and then cooled at a cooldown rate less than 5° C./second when the curing temperature is between 1250° C. and 1150° C., less than 20° C./second when the curing temperature is between 1150° C. and 1100° C., and less than 50° C./second when the curing temperature is between 1100° C. and 800° C.

Abstract: A method for fabricating an interconnection structure includes providing a substrate, forming a dielectric layer on the substrate, forming a conductive structure in the dielectric layer, forming a cap layer doped with silicon on the conductive structure and the dielectric layer, and performing an annealing process on the conductive structure and the cap layer. During the annealing process, the silicon ions in the cap layer react with the material of the conductive structure and form chemical bonds. As such, the connection strength between the cap layer and the conductive structure is improved, which is conducive to suppressing electro migration in the formed interconnection structure. Therefore, the reliability of the formed interconnection structure is improved.

Abstract: A fabrication method of a nitride underlayer structure includes, during AlN layer sputtering with PVD, a small amount of non-Al material is doped to form nitride with decomposition temperature lower than that of AlN. A high-temperature annealing is then performed. After annealing, the AlN layer has a rough surface with microscopic ups and downs instead of a flat surface. By continuing AlGaN growth via MOCVD over this surface, the stress can be released via 3D-2D mode conversion, thus improving AlN cracks.

Abstract: A method of planarizing a roughened surface of a SiC substrate includes: forming a sacrificial material on the roughened surface of the SiC substrate, the sacrificial material having a density between 35% and 120% of the density of the SiC substrate; implanting ions through the sacrificial material and into the roughened surface of the SiC substrate to form an amorphous region in the SiC substrate; and removing the sacrificial material and the amorphous region of the SiC substrate by wet etching.

Abstract: Flash light is emitted from flash lamps to the surface of a semiconductor substrate on which a metal layer has been formed for one second or less to momentarily raise temperature on the surface of the semiconductor substrate including the metal layer and an impurity region to a processing temperature of 1000° C. or more. Heat treatment is performed by emitting flash light to the surface of the semiconductor substrate in a forming gas atmosphere containing hydrogen. By heating the surface of the semiconductor substrate to a high temperature in the forming gas atmosphere for an extremely short time period, contact resistance can be reduced without desorbing hydrogen taken in the vicinity of an interface of a gate oxide film for hydrogen termination.

Abstract: A manufacturing method of a semiconductor device is provided by forming a trench in a surface of a SiC substrate, positioning a protective substrate to cover the trench, and annealing the SiC substrate and the protective substrate.

Abstract: Image sensors may include a plurality of photodiodes. The photodiodes may be isolated from each other using isolations regions formed from p-well or n-well implants. Deep and narrow isolation regions may be formed using a multi-step process that selectively places implants at desired depths in a substrate. If desired, the multi-step process may include only one photolithographic patterning step, which in turn can help reduce costs, fabrication time, and alignment errors. The process may include passing ions through a stack of alternating layers of material such as alternating layers of oxide and nitride. After each implant, a layer in the stack may be removed and ions may be passed through the layers remaining in the stack to form an implant at a different depth in the substrate.

Abstract: According to one embodiment, a nitride semiconductor device includes semiconductor stacked layers provided on a substrate and including a nitride semiconductor; a source electrode and a drain electrode provided on the layers and being in contact with the layers; and a gate electrode provided on the layers and provided between the source electrode and the drain electrode. The layers have a first barrier layer, a second barrier layer, and a carrier running layer interposed between the first barrier layer and the second barrier layer. The second barrier layer and the carrier running layer are removed in a region in which the source electrode on the layers is provided. A part of the source electrode is in contact with the first barrier layer. And another part of the source electrode other than the part of the source electrode is in contact with the second barrier layer.

Abstract: The present invention is generally directed to methods of selectively doping a substrate and the resulting selectively doped substrates. The methods include doping an epilayer of a substrate with the selected doping material to adjust the conductivity of either the epilayers grown over a substrate or the substrate itself. The methods utilize lithography to control the location of the doped regions on the substrate. The process steps can be repeated to form a cyclic method of selectively doping different areas of the substrate with the same or different doping materials to further adjust the properties of the resulting substrate.

Abstract: Methods of forming semiconductor devices are provided by forming a semiconductor layer on a semiconductor substrate. A mask is formed on the semiconductor layer. Ions having a first conductivity type are implanted into the semiconductor layer according to the mask to form implanted regions on the semiconductor layer. Metal layers are formed on the implanted regions according to the mask. The implanted regions and the metal layers are annealed in a single step to respectively activate the implanted ions in the implanted regions and provide ohmic contacts on the implanted regions. Related devices are also provided.

Abstract: Photonic integrated circuits on silicon are disclosed. By bonding a wafer of compound semiconductor material as an active region to silicon and removing the substrate, the lasers, amplifiers, modulators, and other devices can be processed using standard photolithographic techniques on the silicon substrate. A silicon laser intermixed integrated device in accordance with one or more embodiments of the present invention comprises a silicon-on-insulator substrate, comprising at least one waveguide in a top surface, and a compound semiconductor substrate comprising a gain layer, the compound semiconductor substrate being subjected to a quantum well intermixing process, wherein the upper surface of the compound semiconductor substrate is bonded to the top surface of the silicon-on-insulator substrate.

Abstract: Embodiments of the present disclosure generally relate to doping and annealing substrates. The substrates may be doped during a hot implantation process, and subsequently annealed using a nanosecond annealing process. The combination of hot implantation and nanosecond annealing reduces lattice damage of the substrates and facilitates a higher dopant concentration near the surface of the substrate to facilitate increased electrical contact with the substrate. An optional capping layer may be placed over the substrate to reduce outgassing of dopants or to control dopant implant depth.

Abstract: An apparatus for uniform reactive thermal treatment of thin-film materials includes a chamber enclosing a tube shaped space filled with a work gas and heaters disposed outside the chamber. The apparatus further includes a loading configuration for subjecting a plurality of planar substrates to the work gas in the tube shaped space. Baffles are disposed above and below the loading configuration.

Abstract: A method selectively diffuses dopants into a substrate wafer. The method comprises blanket depositing a doped liquid precursor including dopants on a surface of the substrate wafer to create a doped film on the surface of the substrate wafer, selectively forming a diffusion source in the doped film to selectively diffuse the dopants into the substrate wafer, and heating the doped film on the substrate wafer, wherein said heating the doped film diffuses the dopants from the doped film into the substrate wafer.

Abstract: A method for embedding a dopant into a glass substrate is provided. The method may include the steps of applying the dopant to a surface of the glass substrate, positioning the glass substrate adjacent to a catalyst such that the dopant is intermediate the catalyst and the glass substrate, heating the glass substrate to a first temperature, operating a directed thermal energy source so as to generate thermal energy incident upon the dopant, reducing the temperature of the glass substrate to a second temperature below the first temperature, and holding the glass substrate at the second temperature for at least a period of time.

Abstract: Improved complementary doping methods are described herein. The complementary doping methods generally involve inducing a first and second chemical reaction in at least a first and second portion, respectively, of a dopant source, which has been disposed on a thin film of a semiconductor or semimetal material. The chemical reactions result in the introduction of an n-type dopant, a p-type dopant, or both from the dopant source to each of the first and second portions of the thin film of the semiconductor or semimetal. Ultimately, the methods produce at least one n-type and at least one p-type region in the thin film of the semiconductor or semimetal.

Abstract: A disposable dielectric spacer is formed on sidewalls of a disposable material stack. Raised source/drain regions are formed on planar source/drain regions by selective epitaxy. The disposable dielectric spacer is removed to expose portions of a semiconductor layer between the disposable material stack and the source/drain regions including the raised source/drain regions. Dopant ions are implanted to form source/drain extension regions in the exposed portions of the semiconductor layer. A gate-level dielectric layer is deposited and planarized. The disposable material stack is removed and a gate stack including a gate dielectric and a gate electrode fill a cavity formed by removal of the disposable material stack. Optionally, an inner dielectric spacer may be formed on sidewalls of the gate-level dielectric layer within the cavity prior to formation of the gate stack to tailor a gate length of a field effect transistor.

Abstract: Methods of forming a semiconductor structure include the use of channeled implants into silicon carbide crystals. Some methods include providing a silicon carbide layer having a crystallographic axis, heating the silicon carbide layer to a temperature of about 300° C. or more, implanting dopant ions into the heated silicon carbide layer at an implant angle between a direction of implantation and the crystallographic axis of less than about 2°, and annealing the silicon carbide layer at a time-temperature product of less than about 30,000° C.-hours to activate the implanted ions.

Abstract: A method of forming a doped region in a III-nitride substrate includes providing the III-nitride substrate and forming a masking layer having a predetermined pattern and coupled to a portion of the III-nitride substrate. The III-nitride substrate is characterized by a first conductivity type and the predetermined pattern defines exposed regions of the III-nitride substrate. The method also includes heating the III-nitride substrate to a predetermined temperature and placing a dual-precursor gas adjacent the exposed regions of the III-nitride substrate. The dual-precursor gas includes a nitrogen source and a dopant source. The method further includes maintaining the predetermined temperature for a predetermined time period, forming p-type III-nitride regions adjacent the exposed regions of the III-nitride substrate, and removing the masking layer.

Abstract: First, a substrate with a recess is provided in a semiconductor process. Second, an embedded SiGe layer is formed in the substrate. The embedded SiGe layer includes an epitaxial SiGe material which fills up the recess. Then, a pre-amorphization implant (PAI) procedure is carried out on the embedded SiGe layer to form an amorphous region. Next, a source/drain implanting procedure is carried out on the embedded SiGe layer to form a source doping region and a drain doping region. Later, a source/drain annealing procedure is carried out to form a source and a drain in the substrate. At least one of the pre-amorphization implant procedure and the source/drain implanting procedure is carried out in a cryogenic procedure below ?30° C.

Abstract: Methods for forming an electronic device having a fluorine-stabilized semiconductor substrate surface are disclosed. In an exemplary embodiment, a layer of a high-? dielectric material is formed together with a layer containing fluorine on a semiconductor substrate. Subsequent annealing causes the fluorine to migrate to the surface of the semiconductor (for example, silicon, germanium, or silicon-germanium). A thin interlayer of a semiconductor oxide may also be present at the semiconductor surface. The fluorine-containing layer can comprise F-containing WSix formed by ALD from WF6 and SiH4 precursor gases. A precise amount of F can be provided, sufficient to bind to substantially all of the dangling semiconductor atoms at the surface of the semiconductor substrate and sufficient to displace substantially all of the hydrogen atoms present at the surface of the semiconductor substrate.

Abstract: A single crystal SiC substrate is produced with low cost in which a polycrystalline SiC substrate with relatively low cost is used as a base material substrate where the single crystal SiC substrate has less strain, good crystallinity and large size. The method including a P-type ion introduction step for implanting P-type ions from a side of a surface Si layer 3 into an SOI substrate 1 in which the surface Si layer 3 and an embedded oxide layer 4 having a predetermined thickness are formed on an Si base material layer 2 to convert the embedded oxide layer 4 into a PSG layer 6 to lower a softening point, and an SiC forming step for heating the SOI substrate 1 having the PSG layer 6 formed therein in an atmosphere hydrocarbon-based gas to convert the surface Si layer 3 into SiC, and thereafter, cooling the resulting substrate to form a single crystal SiC layer 5 on a surface thereof.

Abstract: A semiconductor-device manufacturing method of the present invention includes a step of selectively implanting impurity ions into a surface of an SiC semiconductor layer and forming impurity regions and a step of activating the impurity ions by annealing the SiC semiconductor layer at a temperature of 1400° C. or more when the surface of the SiC semiconductor layer is covered with an insulating film.

Abstract: A manufacturing method for a semiconductor device includes implanting dopants into a silicon carbide substrate, applying a carbon-containing material on at least one surface of the silicon carbide substrate, and heating the silicon carbide substrate having the carbon-containing material applied thereon to form a carbon layer on surfaces of the silicon carbide substrate. The heating is performed in a non-oxidizing atmosphere, and is followed by another heating step for activating the dopants.

Abstract: A thin film transistor includes a gate electrode, a first insulating layer on the gate electrode, a semiconductor layer on the gate electrode and separated from the gate electrode by the first insulating layer, the semiconductor layer including a channel region corresponding to the gate electrode, a source region, and a drain region, a hydrogen diffusion barrier layer on the semiconductor layer, the hydrogen diffusion barrier layer covering the channel region and exposing the source and drain regions, and a second insulation layer on the source and drain regions and on the hydrogen diffusion barrier layer, such that the hydrogen diffusion barrier layer is between the second insulation layer and the channel region.

Abstract: An object of the present invention is to perform temperature setting of a heating plate so that a wafer is uniformly heated in an actual heat processing time. The temperature of a wafer is measured during a heat processing period from immediately after a temperature measuring wafer is mounted on the heating plate to the time when the actual heat processing time elapses. Whether the uniformity in temperature within the wafer is allowable or not is determined from the temperature of the wafer in the heat processing period, and if the determination result is negative, a correction value for a temperature setting parameter of the heating plate is calculated using a correction value calculation model from the measurement result, and the temperature setting parameter is changed.

Abstract: A method of manufacturing a silicon carbide semiconductor device of an embodiment includes: implanting ions in a silicon carbide substrate; performing first heating processing of the silicon carbide substrate in which the ions are implanted; and performing second heating processing of the silicon carbide substrate for which the first heating processing is performed, at a temperature lower than the first heating processing.

Abstract: A method is disclosed for treating a silicon carbide substrate for improved epitaxial deposition thereon and for use as a precursor in the manufacture of devices such as light emitting diodes. The method includes the steps of implanting dopant atoms of a first conductivity type into the first surface of a conductive silicon carbide wafer having the same conductivity type as the implanting ions at one or more predetermined dopant concentrations and implant energies to form a dopant profile, annealing the implanted wafer, and growing an epitaxial layer on the implanted first surface of the wafer.

Abstract: A field effect transistor of an embodiment of the present invention includes, a semiconductor substrate containing Si atoms; a protruding structure formed on the semiconductor substrate; a channel region formed in the protruding structure and containing Ge atoms; an under channel region formed under the channel region in the protruding structure and containing Si and Ge atoms, the Ge composition ratio among Si and Ge atoms contained in the under channel region continuously changing from the channel region side to the semiconductor substrate side; a gate insulating film formed on the channel region; and a gate electrode formed on the gate insulating film on the channel region.

Abstract: There are disclosed herein various implementations of a method and system for ion implantation at high temperature surface equilibrium conditions. The method may include situating a III-Nitride semiconductor body in a surface equilibrium chamber, establishing a gas pressure greater than or approximately equal to a surface equilibrium pressure of the III-Nitride semiconductor body, and heating the III-Nitride semiconductor body to an elevated implantation temperature in the surface equilibrium chamber while substantially maintaining the gas pressure. The method also includes implanting the III-Nitride semiconductor body in the surface equilibrium at the elevated implantation temperature chamber while substantially maintaining the gas pressure, the implanting being performed using an ion implanter interfacing with the surface equilibrium chamber.

Abstract: A semiconductor is formed on a (110) silicon (Si) substrate, with improved electron mobility. Embodiments include semiconductor devices having a silicon carbide (SiC) portion in the nFET channel region. An embodiment includes forming an nFET channel region and a pFET channel region in a Si substrate, such as a (110) Si substrate, and forming a silicon carbide (SiC) portion on the nFET channel region. The SiC portion may be formed by ion implantation of C followed by a recrystallization anneal or by epitaxial growth of SiC in a recess formed in the substrate. The use of SiC in the nFET channel region improves electron mobility without introducing topographical differences between NMOS and PMOS transistors.

Abstract: Semiconductor devices are formed without zipper defects or channeling and through-implantation and with different silicide thicknesses in the gates and source/drain regions, Embodiments include forming a gate on a substrate, forming a nitride cap on the gate, forming a source/drain region in the substrate on each side of the gate, forming a wet cap fill layer on the source/drain region on each side of the gate, removing the nitride cap from the gate, and forming an amorphized layer in a top portion of the gate. Embodiments include forming the amorphized layer by implanting low energy ions.

Abstract: The invention offers a method of producing a semiconductor device that can suppress the worsening of the property due to surface roughening of a wafer by sufficiently suppressing the surface roughening of the wafer in the heat treatment step and a semiconductor device in which the worsening of the property caused by the surface roughening is suppressed. The method of producing a MOSFET as a semiconductor device is provided with a step of preparing a wafer 3 made of silicon carbide and an activation annealing step that performs activation annealing by heating the wafer 3. In the activation annealing step, the wafer 3 is heated in an atmosphere containing a vapor of silicon carbide generated from the SiC piece 61, which is a generating source other than the wafer 3.

Abstract: To provide a temperature control method capable of equivalently maintaining qualities of substrates even when treated substrates are continuously carried in a treatment container in the case in which activation annealing treatment is performed by an electron impact heating method.

Abstract: The present invention relates generally to methods for high throughput and controllable creation of high performance semiconductor substrates for use in devices such as high sensitivity photodetectors, imaging arrays, high efficiency solar cells and the like, to semiconductor substrates prepared according to the methods, and to an apparatus for performing the methods of the invention.

Abstract: Methods for selectively diffusing dopants into a substrate wafer are provided. A liquid precursor is doped with dopants. The liquid precursor is selected from a group comprising monomers, polymers, and oligomers of silicon and hydrogen. The doped liquid precursor is deposited on a surface of the substrate wafer to create a doped film. The doped film is heated on the substrate wafer for diffusing the dopants from the doped film into the substrate wafer at different diffusion rates to create a heavily diffused region and a lightly diffused region in the substrate wafer. The method disclosed herein further comprises selective curing of the doped film on the surface of the substrate wafer. The selectively cured doped film acts as a diffusion source for selectively diffusing the dopants into the substrate wafer.

Abstract: A semiconductor device according to an embodiment includes a silicon carbide, a metal silicide formed on the silicon carbide and including a first layer and a second layer having a carbon ratio lower than that of the first layer, and a metallic electrode formed on the metal silicide, wherein the second layer is formed on the first layer, and the second layer is in contact with the metallic electrode, and an average grain diameter of a metal silicide in the second layer is larger than an average grain diameter of a metal silicide in the first layer.

Abstract: The present invention discloses a MEMS device with particles blocking function, and a method for making the MEMS device. The MEMS device comprises: a substrate on which is formed a MEMS device region; and a particles blocking layer deposited on the substrate.

Abstract: A method for reducing the effective thickness of a gate oxide using nitrogen implantation and anneal subsequent to dopant implantation and activation is provided. More particularly, the present invention provides a method for fabricating semiconductor devices, for example, transistors, which include a hardened gate oxide and which may be characterized by a relatively large nitrogen concentration at the polysilicon/gate oxide interface and a relatively small nitrogen concentration within the gate oxide and at the gate oxide/substrate interface. Additionally, the present invention provides a method for fabricating a semiconductor device having a metal gate strap (e.g., a metal silicide layer) disposed over the polysilicon layer thereof, which device includes a hardened gate oxide and which may be characterized by a relatively large nitrogen concentration at the silicide/polysilicon interface to substantially prevent cross-diffusion.

Abstract: A silicon carbide substrate having a surface is prepared. An impurity region is formed by implanting ions from the surface into the silicon carbide substrate. Annealing for activating the impurity region is performed. The annealing includes the step of applying first laser light having a first wavelength to the surface of the silicon carbide substrate, and the step of applying second laser light having a second wavelength to the surface of the silicon carbide substrate. The silicon carbide substrate has first and second extinction coefficients at the first and second wavelengths, respectively. A ratio of the first extinction coefficient to the first wavelength is higher than 5×105/m. A ratio of the second extinction coefficient to the second wavelength is lower than 5×105/m. Consequently, damage to the surface of the silicon carbide substrate during laser annealing can be reduced.

Abstract: A method including a phosphorous ion introduction step for implanting phosphorous ions from a side of a surface Si layer into an SOI substrate in which the surface Si layer and an embedded oxide layer having a predetermined thickness are formed on an Si base material layer to convert the embedded oxide layer into a PSG layer to lower a softening point. An SiC forming step is performed by heating the SOI substrate having the PSG layer formed therein in an atmosphere of hydrocarbon-based gas to convert the surface Si layer into SiC. Thereafter, the resulting substrate is cooled to form a single crystal SiC layer on a surface thereof.

Abstract: In various embodiments, semiconductor structures and methods to manufacture these structures are disclosed. In one embodiment, a method to manufacture a semiconductor structure includes forming a cavity in a substrate. A portion of the substrate is doped, or a doped material is deposited over a portion of the substrate. At least a portion of the doped substrate or at least a portion of the doped material is converted to a dielectric material to enclose the cavity. The forming of the cavity may occur before or after the doping of the substrate or the depositing of the doped material. Other embodiments are described and claimed.