59 results about "Dopant Activation" patented technology

A horizontal germanium silicon heterostructure photodetector comprising a horizontal germanium p-i-n diode disposed over a horizontal parasitic silicon p-i-n diode uses silicon contacts for electrically coupling to the germanium p-i-n through the p-type doped and n-type doped regions in the silicon p-i-n without requiring direct physical contact to germanium material. The current invention may be optically coupled to on-chip and/or off-chip optical waveguide through end-fire or evanescent coupling. In some cases, the doping of the germanium p-type doped and/or n-type doped region may be accomplished based on out-diffusion of dopants in the doped silicon material of the underlying parasitic silicon p-i-n during high temperature steps in the fabrication process such as, the germanium deposition step(s), cyclic annealing, contact annealing and/or dopant activation.

Methods are disclosed of making linear and cross-linked, HMW (high molecular weight) polysilanes and polygermanes, polyperhydrosilanes and polyperhydrogermanes, functional liquids containing the same, and methods of using the liquids in a range of desirable applications. The silane and germane polymers are generally composed of chains of Si and/or Ge substituted with R′ substituents, where each instance of R′ is, for example, independently hydrogen, halogen, alkenyl, alkynyl, hydrocarbyl, aromatic hydrocarbyl, heterocyclic aromatic hydrocarbyl, SiR″₃, GeR″₃, PR″₂, OR″, NR″₂, or SR″; where each instance of R″ is independently hydrogen or hydrocarbyl. The cross-linked polymers can be synthesized by dehalogenative coupling or dehydrocoupling. The linear polymers can be synthesized by ring-opening polymerization. The polymers can be further modified by halogenation and/or reaction with the source of hydride to furnish perhydrosilane and perhydrogermane polymers, which are used in liquid ink formulations. The synthesis allows for tuning of the liquid properties (e.g., viscosity, volatility, and surface tension). The liquids can be used for deposition of films and bodies by spincoating, inkjetting, dropcasting, etc., with or without the use of UV irradiation. The deposited films can be converted into amorphous and polycrystalline silicon or germanium, and silicon or germanium oxide or nitride by curing at 400-600 DEG C. and (optionally) laser- or heat-induced crystallization (and/or dopant activation, when dopant is present).

A method of forming a field effect transistor creates shallower and sharper junctions, while maximizing dopant activation in processes that are consistent with current manufacturing techniques. More specifically, the invention increases the oxygen content of the top surface of a silicon substrate. The top surface of the silicon substrate is preferably cleaned before increasing the oxygen content of the top surface of the silicon substrate. The oxygen content of the top surface of the silicon substrate is higher than other portions of the silicon substrate, but below an amount that would prevent epitaxial growth. This allows the invention to epitaxially grow a silicon layer on the top surface of the silicon substrate. Further, the increased oxygen content substantially limits dopants within the epitaxial silicon layer from moving into the silicon substrate.

Structures to reduce dopant activation temperatures for ion implantation in III-N transistors, using low aluminum content layers in proximity to the conducting channel, are disclosed. A method to increase the temperature at which structures can be annealed by annealing in an active nitrogen ambient, for example, in NH₃ in a metalorganic chemical vapor deposition (MOCVD) chamber, is also disclosed.

The invention includes methods of forming field effect transistors. In one implementation, the invention encompasses a method of forming a field effect transistor on a substrate, where the field effect transistor comprises a pair of conductively doped source/drain regions, a channel region received intermediate the pair of source/drain regions, and a transistor gate received operably proximate the channel region. Such implementation includes conducting a dopant activation anneal of the pair of source/drain regions prior to depositing material from which a conductive portion of the transistor gate is made. Other aspects and implementations are contemplated.

Disclosed is a heat treatment system for semiconductor devices. The heat treatment system is used in a heat treatment process for semiconductor devices, such as a crystallization process for an amorphous silicon thin film or a dopant activation process for a poly-crystalline silicon thin film formed on a surface of a glass substrate of a flat display panel including a liquid crystal display (LCD) or an organic light emitting device (OLED). The heat treatment system transfers a semiconductor device after uniformly preheating the semiconductor device in order to prevent deformation of the semiconductor device during the heat treatment process, rapidly performs the heat treatment process under the high temperature condition by heating the semiconductor device using a lamp heater and induction heat derived from induced electromotive force, and unloads the semiconductor device after uniformly cooling the semiconductor device such that the semiconductor device is prevented from being deformed when the heat treatment process has been finished. The heat treatment system rapidly performs the heat treatment process while preventing deformation of the semiconductor device by gradually heating or cooling the semiconductor device.

In one embodiment, the invention generally provides a method for annealing a doped layer on a substrate including depositing a polycrystalline layer to a gate oxide layer and implanting the polycrystalline layer with a dopant to form a doped polycrystalline layer. The method further includes exposing the doped polycrystalline layer to a rapid thermal anneal to readily distribute the dopant throughout the polycrystalline layer. Subsequently, the method includes exposing the doped polycrystalline layer to a laser anneal to activate the dopant in an upper portion of the polycrystalline layer.

The present invention relates to methods and apparatuses for heat treatment of semiconductor films upon thermally susceptible non-conducting substrates at a minimum thermal budget are required, and more particularly, to a polycrystalline silicon thin-film transistors (poly-Si TFTs) and PN diodes on glass substrates for various applications of liquid crystal displays (LCDs), organic light emitting diodes (OLEDs), and solar cells. According to the methods and apparatus of the present invention, the semiconductor films can be heat-treated without damaging the thermally susceptible substrates; e.g., crystallization of amorphous silicon films at the minimum thermal budget acceptable for the use of glass, enhancing kinetics of dopant activation at the minimum thermal budget acceptable for the use of glass.

In PMOS having a gate electrode 7 of a p-type polysilicon film 5 along with a silicon nitride film 13, boron diffusion from the p-type polysilicon film 5 and boron punching through the gate oxide film 4 are prevented, thereby stabilizing the properties of the PMOS. Hydrogen existing in the silicon nitride film 13 accelerates boron diffusion from the film 5. To prevent it, all subsequent steps after the step of forming the silicon nitride film 13 are effected within a temperature range within which the boron diffusion is not accelerated by hydrogen. Forming the silicon oxide film 14 through reduced pressure CVD is effected in a furnace at a temperature lower than 850.degree. C. Annealing for dopant activation in the compensation region 17 to be formed on the substrate in the bottom of the contact hole 16 is effected in a manner of RTA (rapid thermal annealing) at a temperature lower than 1000.degree. C.

By performing a laser-based or flash-based anneal process after silicidation, the degree of dopant activation with reduced diffusion activity may be accomplished, while the characteristics of the metal silicide may be improved or the complexity for manufacturing the same may be reduced.

The present invention relates to apparatuses for continuous and efficient heat-treatment of semiconductor films upon thermally susceptible non-conducting substrates at a minimum thermal budget, and more particularly, to a polycrystalline silicon thin-film transistors (poly-Si TFTs) and PN diodes on glass substrates for various applications of liquid crystal displays (LCDs), organic light emitting diodes (OLEDs), and solar cells. According to the apparatuses of the present invention, the semiconductor films can be heat-treated without damaging the thermally susceptible substrates: e.g., crystallization of amorphous silicon films at the minimum thermal budget acceptable for the use of glass, enhancing kinetics of dopant activation at the minimum thermal budget acceptable for the use of glass.

A CMOS structure is formed on a semiconductor substrate that includes first and second regions having an nFET and a pFET respectively formed thereon. Each nFET and pFET device is provided with a gate, a source and drain, and a channel formed on the substrate. A high permittivity dielectric layer formed on top of the channel is superimposed to the permittivity dielectric layer. The pFET gate includes a thick metal nitride alloy layer or rich metal nitride alloy or carbon metal nitride layer that provides a controlled WF. Superimposed to the permittivity dielectric layer, the nFET gate is provided with a thin metal nitride alloy layer, enabling to control the WF. A metal deposition is formed on top of the respective nitride layers. The gate last approach characterized by having a high thermal budget smaller than 500° C. used for post metal deposition, following the dopant activation anneal.

Disclosed are embodiments of a semiconductor wafer processing method that allow device regions to be selectively annealed following back end of the line (BEOL) metal wiring formation without degrading wiring layer reliability. In the embodiments, a semiconductor device is formed adjacent to the top surface of a wafer such that it incorporates a selectively placed infrared absorbing layer (IAL). Then, following BEOL metal wiring formation, the bottom surface of the wafer is exposed to an infrared light having a wavelength that is transparent to the wafer. The infrared light is absorbed by and, thereby heats up the IAL to a first predetermined temperature (e.g., a dopant activation temperature, a temperature required for a state change, etc.). The resulting heat is transferred from the IAL to an adjacent region of the semiconductor device without raising the temperature of the metal wiring above a second predetermined temperature (e.g., a temperature that could degrade the metal wiring) that is lower than the first predetermined temperature.

A method of enhancing dopant activation without suffering additional dopant diffusion, includes forming shallow and lightly-doped source/drain extension regions in a semiconductor substrate, performing a first anneal process on the source/drain extension regions, forming deep and heavily-doped source/drain regions in the substrate adjacent to the source/drain extension regions, and performing a second anneal process on source/drain regions. The first anneal process is a flash anneal process performed for a time of between about 1 millisecond and 3 milliseconds, and the second anneal process is a rapid thermal anneal process performed for a time of between about 1 second and 30 seconds.

A method for forming a semiconductor structure includes providing a semiconductor substrate; forming a gate stack over the semiconductor substrate; implanting carbon into the semiconductor substrate; and implanting an n-type impurity into the semiconductor substrate to form a lightly doped source/drain (LDD) region, wherein the n-type impurity comprises more than one phosphorous atom. The n-type impurity may include phosphorous dimer or phosphorous tetramer.

A materials processing system comprises a thermal processing chamber including a heating source, a first noncontacting thermal measurement device positioned to measure temperature on a first area of the material being processed, and, a second noncontacting thermal measurement device positioned to measure temperature on a second area of the material being processed, the first device being relatively more sensitive to changes in surface emissivity than the second device. By comparing the outputs of the two devices, emissivity changes can be detected and used as a proxy for some physical change in the workpiece and thereby determine when the desired process has been completed. The system may be used to develop a process recipe, or it may be part of a system for real-time process control based on emissivity changes. Applicable processes include heating, annealing, dopant activation, silicide formation, carburization, nitridation, sintering, oxidation, vapor deposition, metallization, and plating.

Disclosed are methods of forming field effect transistor(s) (FET) and the resulting structures. Instead of forming the FET source/drain (S/D) regions during front end of the line (FEOL) processing, they are formed during middle of the line (MOL) processing through metal plug openings in an interlayer dielectric (ILD) layer. Processes used to form the S/D regions through the metal plug openings include S/D trench formation, epitaxial semiconductor material deposition, S/D dopant implantation and S/D dopant activation, followed by silicide and metal plug formation. Since the post-MOL processing thermal budget is low, the methods ensure reduced S/D dopant deactivation, reduced S/D strain reduction, and reduced S/D dopant diffusion and, thus, enable reduced S/D resistance, optimal strain engineering, and flexible junction control, respectively. Since the S/D regions are formed through the metal plug openings, the methods eliminate overlay errors that can lead to uncontacted or partially contacted S/D regions.

By performing multiple radiation-based anneal processes on the basis of less critical process parameters, the overall risk for creating anneal-induced damage, such as melting of gate portions, may be substantially avoided while nevertheless the respective degree of dopant activation may be enhanced for each individual anneal process. Consequently, the sheet resistance of advanced transistor devices may be reduced with a decreasing number of sequential anneal processes.

In a method for crystallization or dopant activation heat treatment of a semiconductor film upon a thermally susceptible non-conducting substrate lying onto a susceptor, an induction coil is disposed in close proximity of the semiconductor film and disposed with the electrical current direction of the coil aligned parallel to the in-plane direction of the semiconductor film, a magnetic core is disposed around the coil to strengthen and concentrate a magnetic field generated by the coil onto the semiconductor film, and an alternating electrical current is introduced in the induction coil to generate an alternating magnetic field through the semiconductor film heated by the susceptor to the extent that the semiconductor film can be induction-heated.

An image display device capable of high-resolution and smooth moving image display, equipped with TFTs in an n-type (or p-type) semiconductor layer with a high on-off ratio and a low resistance. In polysilicon crystallization by laser annealing, an n-type (or p-type) semiconductor layer with a low resistance is produced by performing the following processes in order: implanting nitrogen (N) ions into an amorphous silicon precursor semiconductor film; laser crystallization; implanting n-type (or p-type) dopant ions; and annealing for dopant activation. When fabricating TFTs, this low-resistance semiconductor layer is used to form a source and a drain. Since C, N, and O impurities decrease the mobility of the TFTs, polysilicon is used in which the contaminants concentrations meet the following conditions: carbon concentration ≦3×10¹⁹ cm⁻³, nitrogen concentration ≦5×10¹⁷ cm⁻³, and oxygen concentration ≦3×10¹⁹ cm⁻³.

Methods are disclosed for activating dopants in a doped semiconductor substrate. A carbon precursor is flowed into a substrate processing chamber within which the doped semiconductor substrate is disposed. A plasma is formed from the carbon precursor in the substrate processing chamber. A carbon film is deposited over the substrate with the plasma. A temperature of the substrate is maintained while depositing the carbon film less than 500° C. The deposited carbon film is exposed to electromagnetic radiation for a period less than 10 ms, and has an extinction coefficient greater than 0.3 at a wavelength comprised by the electromagnetic radiation.

A method of manufacturing a MOSFET semiconductor device comprises forming a gate electrode over a substrate and a gate oxide between the gate electrode and the substrate; forming source/drain extensions in the substrate; forming first and second sidewall spacers; implanting dopants within the substrate to form source/drain regions in the substrate adjacent to the sidewalls spacers; laser thermal annealing to activate the source/drain regions; depositing a layer of nickel over the source/drain regions; and annealing to form a nickel silicide layer disposed on the source/drain regions. The source/drain extensions and sidewall spacers are adjacent to the gate electrode. The source/drain extensions can have a depth of about 50 to 300 angstroms, and the source/drain regions can have a depth of about 400 to 1000 angstroms. The annealing is at temperatures from about 350 to 500° C.

A new process integration method is described to form heavily doped p⁺ source and drain regions in a CMOS device. After defining the p- and n-well regions on a semiconductor substrate, gate silicon dioxide is deposited and nitrided in a nitrogen-containing atmosphere. Poly-silicon is then deposited and the two NMOS and PMOS gates are formed. For the p⁺ doping of the poly-silicon gate and S/D regions around the PMOS gate, B⁺ ions are then implanted. Cap dielectric layer comprising silicon dioxide is then deposited, followed by dopant activation with high temperature rapid thermal annealing. The cap dielectric layer is then used as resist protective film; it is removed from those areas of the chip that would require formation of electrical contacts. Silicide electrical contacts are then formed in these areas.