Patent application number | Description | Published |
20120032239 | METHOD FOR INTRODUCING CHANNEL STRESS AND FIELD EFFECT TRANSISTOR FABRICATED BY THE SAME - The present invention relates to CMOS ultra large scale integrated circuits, and provides a method for introducing channel stress and a field effect transistor fabricated by the same. According to the present invention, a strained dielectric layer is interposed between source/drain regions and a substrate of a field effect transistor, and a strain is induced in a channel by the strained dielectric layer which directly contacts the substrate, so as to improve a carrier mobility of the channel and a performance of the device. The specific effects of the invention include: a tensile strain may be induced in the channel by using the strained dielectric layer having a tensile strain in order to increase an electron mobility of the channel; a compressive strain may be induced in the channel by using the strained dielectric layer having a compressive strain in order to increase a hole mobility of the channel. According to the invention, not only an effectiveness of the introduction of channel stress is ensued, but the device structure of the field effect transistor is also improved fundamentally, so that a capability for suppressing a short channel effect of the device is increased. | 02-09-2012 |
20120187495 | SEMICONDUCTOR DEVICE AND METHOD FOR FABRICATING THE SAME - The present invention provides a semiconductor device and a method for fabricating the same, wherein the method comprises: providing a germanium-based semiconductor substrate having a plurality of active regions and device isolation regions between the plurality of the active regions, wherein a gate dielectric layer and a gate over the gate dielectric layer are provided on the active regions, and the active regions include source and drain extension regions and deep source and drain regions; performing a first ion implantation process with respect to the source and drain extension regions, wherein the ions implanted in the first ion implantation process include silicon or carbon; performing a second ion implantation process with respect to the source and drain extension regions; performing a third ion implantation process with respect to the deep source and drain regions; performing an annealing process with respect to the germanium-based semiconductor substrate which has been subjected to the third ion implantation process. According to the method for fabricating a semiconductor device, through the implantation of silicon impurities, appropriate stress may be introduced into the germanium channel effectively by the mismatch of lattices in the source and drain regions, so that the mobility of electrons in the channel is enhanced and the performance of the device is improved. | 07-26-2012 |
20120190202 | METHOD FOR FABRICATING SEMICONDUCTOR NANO CIRCULAR RING - The present invention discloses a method for fabricating a semiconductor nano circular ring. In the method, firstly, a positive photoresist is coated on a semiconductor substrate, then the photoresist is exposed by using a circular mask with a micrometer-sized diameter to obtain the circular ring-shaped photoresist, based on the poisson diffraction principle. Then, a plasma etching is performed on the substrate under a protection of the circular ring-shaped photoresist to form a circular ring-shaped structure with a nano-sized wall thickness on a surface of the substrate. The embodiment of present invention fabricates a nano-sized circular ring-shaped structure by using a micrometer-sized lithography equipment and a micrometer-sized circular mask, and overcomes the dependence on advanced technologies, so as to effectively reduce the fabrication cost of the circular ring-shaped nano structure. | 07-26-2012 |
20120264311 | SURFACE TREATMENT METHOD FOR GERMANIUM BASED DEVICE - The present invention provides a surface treatment method for germanium based device. Through performing surface pretreatment to the germanium based device by using an aqueous solution of ammonium fluoride as a passivant, the interface state may be reduced, the formation of natural oxidation layer at the germanium surface may be inhibited, the regeneration of natural oxidation layer and the out-diffusion of the germanium based substrate material can be effectively inhibited, and the thermal stability of the metal germanide may also be increased significantly, so that the interface quality of the germanium based device is improved easily and effectively, which are advantageous to improve the performance of the germanium based transistor. | 10-18-2012 |
20120289004 | FABRICATION METHOD OF GERMANIUM-BASED N-TYPE SCHOTTKY FIELD EFFECT TRANSISTOR - The present invention discloses a fabrication method of a Ge-based N-type Schottky field effect transistor and relates to a filed of ultra-large-scaled integrated circuit fabrication process. The present invention forms a thin high K dielectric layer between a substrate and a metal source/drain. The thin layer on one hand may block the electron wave function of metal from inducing an MIGS interface state in the semiconductor forbidden band, on the other hand may passivate the dangling bonds at the interface of Ge. Meanwhile, since the insulating dielectric layer has a very thin thickness, and electrons can substantially pass freely, the parasitic resistances of the source and the drain are not significantly increased. The method can weaken the Fermi level pinning effect, cause the Fermi energy level close to the position of the conduction band of Ge and lower the electron barrier, thereby increasing the current switching ratio of the Ge-based Schottky transistor and improve the performance of the NMOS device. | 11-15-2012 |
20130013245 | METHOD FOR OBTAINING DISTRIBUTION OF CHARGES ALONG CHANNEL IN MOS TRANSISTOR - The present invention discloses a method for obtaining a distribution of charges along a channel of a MOS transistor, which is used for obtaining distributions of interface states charges and charges of a gate dielectric layer in the MOS transistor. The method includes: adding a MOS transistor into a test circuit; measuring two charge pumping current curves when a source terminal is open-circuited or when a drain terminal is open-circuited before and after a stress is applied by using a charge pumping current test method, where one of the two charge pumping current curves is an original curve and the other one is an post-stress curve; finding a point B corresponding to a point A on the original curve on the post-stress curve, and estimating amount of locally-generated interface states charges and charges of the gate dielectric layer by a variation of the charge pumping current and a variation in a voltage at a local point. As compared with a conventional method for obtaining a distribution, the method of the present invention can obtain a distribution of charges along a direction form the drain or source terminal to the channel more easily and rapidly, with an aid of a computer. A mass of complicated and repeated tests are reduced. Also, the method can provide an effective base for improving device reliability. | 01-10-2013 |
20130043515 | Strained Channel Field Effect Transistor and the Method for Fabricating the Same - The present invention discloses a strained channel field effect transistor and a method for fabricating the same. The field effect transistor comprises a substrate, a source/drain, a gate dielectric layer, and a gate, characterized in that, an “L” shaped composite isolation layer, which envelops a part of a side face of the source/drain adjacent to a channel and the bottom of the source/drain, is arranged between the source/drain and the substrate; the composite isolation layer is divided into two layers, that is, an “L” shaped insulation thin layer contacting directly with the substrate and an “L” shaped high stress layer contacting directly with the source and the drain. The field effect transistor of such a structure improves the mobility of charge carriers by introducing stress into the channel by means of the high stress layer, while fundamentally improving the device structure of the field effect transistor and improving the short channel effect suppressing ability of the device. | 02-21-2013 |
20130069126 | GERMANIUM-BASED NMOS DEVICE AND METHOD FOR FABRICATING THE SAME - An embodiment of the invention provides a germanium-based NMOS device and a method for fabricating the same, which relates to fabrication process technology of an ultra-large-scale-integrated (ULSI) circuit. The germanium-based NMOS device has two dielectric layer interposed between a metal source/drain and a substrate. The bottom dielectric layer includes a dielectric material having a high pinning coefficient S such as hafnium oxide, silicon nitride, hafnium silicon oxide or the like, and the top dielectric layer includes a dielectric material having a low conduction band offset ΔE | 03-21-2013 |
20130103351 | Method for Predicting Reliable Lifetime of SOI Mosfet Device - Disclosed herein is a method for predicting a reliable lifetime of a SOI MOSFET device. The method comprises: measuring a relationship of a gate resistance of the SOI MOSFET device varying as a function of a temperature at different wafer temperatures; performing a lifetime accelerating test on the SOI MOSFET device at different wafer temperatures, so as to obtain a degenerating relationship of a parameter representing the lifetime of the device as a function of stress time, and obtain a lifetime in the presence of self-heating when the parameter degenerates to 10%; performing a self-heating correction on the measured lifetime of the device by using the measured self-heating temperature and an Arrhenius model, so as to obtain a lifetime without self-heating influence; performing a self-heating correction on a variation of the drain current caused by self-heating; performing a self-heating correction on an impact ionization rate caused by hot carriers; and predicting the lifetime of the SOI MOSFET device under a bias. The embodiment of the invention prevents the self-heating effect from affecting the SOI MOSFET device in a practical logic circuit or in an AC analog circuit, which leads to a more precise prediction result. | 04-25-2013 |
20130119445 | CMOS DEVICE FOR REDUCING RADIATION-INDUCED CHARGE COLLECTION AND METHOD FOR FABRICATING THE SAME - A CMOS device for reducing a radiation-induced charge collection and a method for fabricating the same. In the CMOS device, a heavily doped charge collection-suppressed region is disposed directly under the source region and the drain region. The region has a doping type opposite that of the source region and the drain region, and has a doping concentration not less than that of the source region and the drain region. The charge collection-suppressed region has a lateral part slightly less than or equal to that of the source region and the drain region, and has a lateral range toward to the channel not exceed the edges of the source region and the drain region. The CMOS device may greatly reduce a range of the funnel that appears under the action of a single particle, so that charges collected instantaneously under a force of an electric field may be reduced. | 05-16-2013 |
20130161757 | CMOS Device for Reducing Charge Sharing Effect and Fabrication Method Thereof - The present invention discloses a CMOS device of reducing charge sharing effect and a fabrication method thereof. The present invention has an additional isolation for trapping carriers disposed right below an isolation region. the material of the additional isolation region is porous silicon. Since porous silicon is a functional material of spongy structure by electrochemistry anodic oxidizing monocrystalline silicon wafer, there are a large number of microvoids and dangling bonds on the surface layer of the porous silicon. These defects may form defect states in a center of forbidden band of the porous silicon, the defect states may trap carriers so as to cause an increased resistance. And with an increase of density of corrosion current, porosity increases, and defects in the porous silicon increase. The present invention can reduce the charge sharing effect due to heavy ions by using a feature that the defect states in the porous silicon trap carriers, the formation of a shallow trench isolation (STI) region and a isolation region underneath only needs one time photolithography, and the process is simple, so that radioresistance performance of an integrated circuit may be greatly increased. | 06-27-2013 |
20130309875 | INTERFACE TREATMENT METHOD FOR GERMANIUM-BASED DEVICE - Disclosed herein is an interface treatment method for germanium-based device, which belongs to the field of manufacturing technologies of ultra large scaled integrated (ULSI) circuits. In the method, the natural oxide layer on ther surface of the germanium-based substrate is removed by using a concentrated hydrochloric acid solution having a mass percentage concentration of 15%˜36%, and dangling bonds of the surface are performed a passivation treatment by using a diluted hydrochloric acid solution having a mass percentage concentration of 5%˜10% so as to form a stable passivation layer on the surface. This method makes a good foundation for depositing a high-K (high dielectric constant) gate dielectric on the surface of the germanium-based substrate after cleaning and passivating, enhances quality of the interface between the gate dielectric and the substrate, and improves the electrical performance of germanium-based MOS device. | 11-21-2013 |
20140117465 | GE-BASED NMOS DEVICE AND METHOD FOR FABRICATING THE SAME - The embodiments of the present invention provide a Ge-based NMOS device structure and a method for fabricating the same. By using the method, double dielectric layers of germanium oxide (GeO | 05-01-2014 |
20150014765 | RADIATION RESISTANT CMOS DEVICE AND METHOD FOR FABRICATING THE SAME - A radiation resistant CMOS device and a method for fabricating the same. The CMOS device includes a substrate, a source region, a drain region and a vertical channel on the substrate. A first dielectric protection region is inserted into the vertical channel at the center of the vertical channel to divide the vertical channel into two parts and has a height equal to the length of the vertical channel. The edge of the first dielectric protection region is 20-100 nm from an outer side of the channel, with a central axis of an silicon platform for an active region as the center. A second dielectric protection region is disposed under the source or drain region, with a length equal to the length of the source or drain region and a height of 10-50 nm. The dielectric protection regions effectively block paths for the source and drain regions collecting charges. | 01-15-2015 |
20150031188 | METHOD FOR ISOLATING ACTIVE REGIONS IN GERMANIUM-BASED MOS DEVICE - Disclosed herein is a method for isolating active regions in a germanium-based MOS device. A surface of a germanium-based substrate is covered by a thin polysilicon layer or a poly-SiGe layer, and an isolation structure of germanium dioxide covered by a silicon dioxide layer or a SiGe oxide layer on top is formed by means of two steps of oxidation in a case of the active regions are protected. Such two steps of oxidation using the polysilicon layer or the poly-SiGe layer as a sacrificial layer is advantageous to improve the isolation quality of a fabricated germanium dioxide and to reduce a beak effect occurred during a local field oxygen oxidation so as to dramatically elevate the performance of the germanium device. | 01-29-2015 |