Abstract: Methods of fabricating leadless packages are described that provide good solder joint reliability. In most respects, the packages are fabricated in a manner similar to current lead frame based leadless packaging techniques. However, at some point in the process, the contacts are provided with undercut regions that are left exposed during solder plating so that the solder plating also covers the exposed side and undercut segments of the contacts. When the resultant devices are soldered to an appropriate substrate (after singulation), each resulting solder joint includes a fillet that adheres very well to the undercut portion of contact. This provides a high quality solder joint that can be visually inspected from the side of the package.

Abstract: A method for applying a protective coating on an article, comprising the following steps: selecting an article with a surface for applying a coating thickness; creating undercut grooves on the article, where the grooves depend beneath the surface to a bottom portion with the grooves having an upper width on the surface and a lower width on the bottom portion connected by side walls, where at least one of the side walls connects the upper width and the lower width to form an undercut angle with the surface less than 90°; and, applying the protective coating onto the article to fill the undercut grooves and cover the surface, thereby forming weak paths within the protective coating.

Abstract: PbZr0.52Ti0.48O3 (PZT) films of thickness ∼1μm prepared by a sol-gel process were wet-chemically patterned using an economical and effective etch process. The etch recipe provided excellent etch control, minimized undercut, preserved the photoresist mask, and effectively removed the residues on the etched surfaces. A high etch rate (200nm∕min), high selectivity with respect to photoresist, and limited undercutting (1.5:1, lateral: thickness) were obtained. The patterned PZT films exhibited good ferroelectric properties in terms of larger saturation polarization, Pmax of ∼53μC∕cm2 at an applied field of 1MV∕cm, higher remnant polarization Pr of ∼30μC∕cm2 for a coercive field of ∼150kV∕cm, fatigue-free characteristics up to ⩾1010 switching cycles, and a low leakage current density of 10−6A∕cm2 at 200×105kV∕cm.

Abstract: A wafer level chip scale package may have a gap provided between a solder bump and a bump land. The gap may be filled with a gas. A method of manufacturing a wafer level chip scale package may involve forming a redistribution line having a first opening, forming a seed metal layer having a second opening including an undercut portion, and forming the gap using the first and the second openings.

Abstract: As one of the solutions to the limitations of the current layered manufacturing, hybrid rapid prototyping systems that perform both machining and deposition are being introduced. In the hybrid rapid prototyping, a part of a complicated shape is realized by adding layers of a simpler shape, each of which is obtained by machining a sheet of constant thickness from its top and bottom surfaces. Thus it is desired to decompose a given part into the minimum number of layers while guaranteeing each layer to be fabricated from the given sheets using a 3-axis milling machine. To satisfy these requirements, a concave edge-based approach is proposed to decompose a part into layers by considering the tool accessibility, the total number of layers, and the allowable sheet thickness. In this approach, for a given build-up direction, the undercut edges, which cause a part to be inaccessible by a tool, are extracted and classified into two types and eliminated in two decomposition steps.

Abstract: This work reports an easy planarization and passivation approach for the integration of III-V semiconductor devices. Vertically etched III-V semiconductor devices typically require sidewall passivation to suppress leakage currents and planarization of the passivation material for metal interconnection and device integration. It is, however, challenging to planarize all devices at once. This technique offers wafer-scale passivation and planarization that is automatically leveled to the device top in the 1-3-/spl mu/m vicinity surrounding each device. In this method, a dielectric hard mask is used to define the device area. An undercut structure is intentionally created below the hard mask, which is retained during the subsequent polymer spinning and anisotropic polymer etch back. The spin-on polymer that fills in the undercut seals the sidewalls for all the devices across the wafer. After the polymer etch back, the dielectric mask is removed leaving the polymer surrounding each device level with its device top to atomic scale flatness. This integration method is robust and is insensitive to spin-on polymer thickness, polymer etch nonuniformity, and device height difference. It prevents the polymer under the hard mask from etch-induced damage and creates a polymer-free device surface for metallization upon removal of the dielectric mask. We applied this integration technique in fabricating an InP-based photonic switch that consists of a mesa photodiode and a quantum-well waveguide modulator using benzocyclobutene (BCB) polymer. We demonstrated functional integrated photonic switches with high process yield of >90%, high breakdown voltage of >25 V, and low ohmic contact resistance of /spl sim/10 /spl Omega/. To the best of our knowledge, such an integration of a surface-normal photodiode and a lumped electroabsorption modulator with the use of BCB is the first to be implemented on a single substrate.

Abstract: Studying the mechanics of nanometer-scale biomolecules presents many challenges; these include maintaining light microscopy image quality and avoiding interference with the laser used for mechanical manipulation, that is, optical tweezers. Studying the pushing forces of a polymerizing filament requires barriers that meet these requirements and that can impede and restrain nanoscale structures subject to rapid thermal movements. We present a flexible technique that meets these criteria, allowing complex barrier geometries with undercut sidewall profiles to be produced on #1 cover glass for the purpose of obstructing and constraining polymerizing filaments, particularly microtubules. Using a two-layer lithographic process we are able to separate the construction of the primary features from the construction of a depth and shape-controlled undercut. The process can also be extended to create a large uniform gap between an SU-8 photoresist layer and the glass substrate. This technique can be easily scaled to produce large quantities of shelf-stable, reusable microstructures that are generally applicable to microscale studies of the interaction of cellular structures with defined microscale features.

Abstract: Embodiments of the invention provide a device with a metal gate, a high-k gate dielectric layer, source/drain extensions a distance beneath the metal gate, and lateral undercuts in the sides of the metal gate.

Abstract: The Miller-indices determination of the arising surfaces at the Si(0 0 1) convex corner due to anisotropic etching is investigated. We propose a 2D zoning model in which the undercut planes arising at a masked convex corner are presumed to be in the same zone as the sidewalls forming the convex corner, which is characterized by the parallelism of the intersection lines of each pair of new surfaces and the sidewalls. Based on this model a method combining the experimental data, analytical geometry and stereographic projection is presented to systematically determine the Miller indices of the arising planes. The quantitative prediction of undercut planes is confirmed by the angle measurement using a surface profiler.

Abstract: PROBLEM TO BE SOLVED: To provide a mold for injection molding which enables simultaneous filling from a plurality of gates and also facilitates takeout even in the case of multiple-impression molding, in regard to the injection molding of a shape having a hollow part demanding high precision, such as a precision component gear SOLUTION: When a first movable plate 13 and a second movable plate 15 are lowered, from a state of closure, to be separated from each other, regulation by locking blocks 45, 45 is canceled and slide blocks 43, 43 slide gradually in the directions of arrows so that they separate from each other When mold opening is completed, the slide blocks 43 are in a state of being moved to the opposite sides By this separation of the slide blocks 43, 43, a second sprue part 85 is opened As a result, a second sprue 75 and a second runner 77 being undercut are exposed and thus takeout is enabled COPYRIGHT: (C)2005,JPO&NCIPI

Abstract: An undercut (50) is provided in a gas turbine engine disk (30) to smooth out an uneven axial distribution of radial stress in the disk (30). The undercut (50) is defined radially inwardly of the blade attachment slots (46) provided at the periphery of the disk (30). A preferred embodiment is described herein the rotor is a swept fan with blades that are asymmetric, thereby causing an uneven axial distribution of radial stress along blade roots and corresponding blade attachment slots. A corresponding method of smoothing out an uneven axial distribution of radial stress in gas turbine engine rotor disk is also disclosed.

Abstract: Undercut and humping bead are the common defects that limit the maximum welding speed of tandem pulsed GMA welding. In order to raise the maximum welding speed, effects of the angle and distance between leading wire and trailing wire on the bead formation of high speed welding are investigated. The undercut and humping bead is attributed to the irregular flow of molten metal towards the rear part of the weld pool. This irregular flow can be prevented by the trailing wire with a push angle from 5 to 13 degrees that provides a proper component of arc force towards the welding direction. Moreover, the irregular flow is also related to the distance between leading wire and trailing wire and the flow becomes regular when the distance is in the range from 9 to 12mm. As a result, the maximum speed of tandem pulsed GMA welding is improved markedly.

Abstract: A molding method and apparatus includes movable die 30 and fixed die 20 which form cavity 50 , and extrusion plate 40 movable in the die closing/opening direction. A die surface 32 b corresponding to the undercut portion is formed by separate push-up block 32 , which is fixed to push-up pin 42 , which is tiltably held by extrusion plate 40 , and passes through insertion hole 34 in movable die 30 . A gap 34 a enables push-up pin 42 to tilt in the insertion hole. Push-up block 32 releases the part from the movable die by relative move-ment between extrusion plate 40 and movable die 30 , and, by further movement of the part, the slanted surface of the undercut portion pushes the die surface of the push-up block in a direction which intersects with the die closing/opening direction to free the undercut portion by tilting the push-up pin and push-up block.

Abstract: PROBLEM TO BE SOLVED: To provide a device and a method for manufacturing an injection-molded article comprising a plate-like body part with a bent cross-sectional shape, and a flange part provided at an end in the inward direction of the body part and formed into an undercut part in molding, which can make the sliding stroke of a slide mold short, while avoiding interference between the slide mold and the flange part when the molded article is taken out. SOLUTION: This device is provided with an extrusion part 51 which protrudes to a position in which an inner edge of the flange part Xa of the molded article X is extruded to the outside of the outer edge of the slide mold 14 in the state of making the slide mold 14 slid to a prescribed position. COPYRIGHT: (C)2007,JPO&INPIT

Abstract: PROBLEM TO BE SOLVED: To provide an electrode mounting structure capable of simply mounting an electrode part on a synthetic resin member, and to enable a molding device for molding the synthetic resin member to be simply constructed. SOLUTION: The electrode part 14 can be simply mounted only by partially deforming a cover (synthetic resin member) 12 by electrode guides 24, 26, a lid part 28, an engaging protrusion 36 or the like. At the same time, in the case of integrally molding the cover 12 having the electrode guides 24, 26, the lid part 28, the engaging protrusion 36 or the like by injection molding by using the molding device provided with a pair of molding dies enabled to come close to and separate from the cover in z-direction, since an opening 30 is formed on upper face 20 of lower side of the lid part 28, an undercut at lower side of the lid part 28 is eliminated, and a sliding mold and a driving mechanism become unnecessary. By the above, the molding device can be simply constructed at low cost. COPYRIGHT: (C)2006,JPO&NCIPI

Abstract: Disclosed are a method, system and apparatus for analyzing foam decomposition in contact mode during mold filling in lost foam casting, the foam decomposition having a foam material vapor fraction and the mold filling having a mold filling speed. The method includes providing a plurality of parameter values for casting process parameters as variables of a plurality of predetermined equations, simultaneously solving the plurality of predetermined equations including the parameter values, calculating a vapor value for the fraction of the foam material that decomposes to vapor, an undercut length value designating the amount of coating exposed to gas diffusion, and a speed value for the mold filling speed, and determining whether to adjust at least one of the parameter values based on the results for the vapor value, the undercut length value, or the speed value.

Abstract: A method for forming a CMOS device in a manner so as to avoid dielectric layer undercut during a pre-silicide cleaning step is described. During formation of CMOS device comprising a gate stack on a semiconductor substrate surface, the patterned gate stack including gate dielectric below a conductor with vertical sidewalls, a dielectric layer is formed thereover and over the substrate surfaces. Respective nitride spacer elements overlying the dielectric layer are formed at each vertical sidewall. The dielectric layer on the substrate surface is removed using an etch process such that a portion of the dielectric layer underlying each spacer remains. Then, a nitride layer is deposited over the entire sample (the gate stack, the spacer elements at each gate sidewall, and substrate surfaces) and subsequently removed by an etch process such that only a portion of said nitride film (the "plug") remains. The plug seals and encapsulates the dielectric layer underlying each said spacer, thus preventing the dielectric material from being undercut during the subsequent pre-silicide clean process. By preventing undercut, this invention also prevents the etch-stop film (deposited prior to contact formation) from coming into contact with the gate oxide. Thus, the integration of thin-spacer transistor geometries, which are required for improving transistor drive current, is enabled.

Abstract: A technique for manufacturing a micro-electro-mechanical (MEM) structure includes a number of steps. Initially, a substrate is provided. Next, a plurality of trenches are etched into the substrate with a first etch. Then, a charging layer is formed at a bottom of each of the trenches to form undercut trenches. Finally, a second etch is provided into the undercut trenches. The charging layer causes the second etch to laterally etch foots in the substrate between the undercut trenches. The footers undercut the substrate to release a portion of the substrate for providing a movable structure between the undercut trenches and above the footers.

Abstract: PROBLEM TO BE SOLVED: To provide a flexible printed circuit with high reliability wherein wiring adhesion strength is high even if forming a micro patterning, and to provide a method of manufacturing the same. SOLUTION: In the method, a photo resist layer is formed on a metal seed layer formed on at least one side of an insulation film, conductor plating is applied to a photo resist pattern obtained by etching the photo resist layer, and the photo resist pattern is exfoliated and removed to form a metal wiring layer, after the photo resist pattern is exfoliated and removed. The side face of the metal wiring layer is etched until an undercut is removed on a lower part of the side face of the metal wiring layer. COPYRIGHT: (C)2007,JPO&INPIT

Abstract: An upper bus electrode is formed as a laminated wire of a metal film lower layer, a metal film intermediate layer and a metal film upper layer. Al lower in electrode potential is used as a low resistance material for the metal film intermediate layer of the upper bus electrode, while Cr high in heat resistance and oxidation resistance and higher in electrode potential than Al is used for the metal film lower and upper layers disposed as upper and lower layers. Al and Cr are selectively etched so that the metal film lower layer projects on one side and has an undercut on the other side with respect to the metal film intermediate layer. Thus, when the upper bus electrode has a structure using a laminated wire made of metal high in heat resistance and oxidation resistance, and metal low in resistance and sandwiched in the metal high in heat resistance and oxidation resistance, so as to separate an upper electrode from upper electrodes by self-alignment, deformation of the undercut portion due to oxidization of a side surface of the low-resistance metal is suppressed to improve the self-alignment separation characteristic of the upper electrode.

Abstract: This paper investigates possible solutions to intensity imbalance minimization for 65nm node application through rigorous vector simulations. It provides a strategic plan to select the right technology for AAPSM application. Technologies such as undercut, bias, combination of undercut and bias and use of a Transparent Etch Stop Layer (TESL) are compared. The study looks at the effect of through pitch, defocus, phase error and sidewall profile on space CD bias for the technologies mentioned to determine the set of conditions that would provide the best compromise between performance and manufacturability. Simulations indicate the use of TESL along with undercut would provide best compromise between manufacturability and performance. Simulation results show that performance can be improved considerably by optimizing phase target. The use of vertical side walls is sufficient if the purpose of simulation is to determine trends. For more accurate simulations it is suggested that the profile used in simulation be matched to profiles seen on manufactured AAPSM.

Abstract: In apparatus for injection molding articles with a rear section, with at least one shaping mold tool element (11) which has a projection for shaping the rear section and is movable in the apparatus (specifically to release the molding), the shaping mold tool element is tiltable.

Abstract: PROBLEM TO BE SOLVED: To provide a molding method for an artificial tooth with aesthetics, and a support hole and a support projection having an undercut as a mechanical supporting means to prevent the tooth from falling down from a baseplate. SOLUTION: In the molding method for artificial tooth, a pasty resin is injected into a cavity formed by a mold of the artificial tooth and polymerized and hardened. The mold can be divided into a base mold made of a silicone rubber and a tooth crown mold. On a part corresponding to the bottom of the artificial tooth in the base mold, projections with an undercut or holes with an undercut for forming support projections in the direction of dividing for forming support holes are provided. COPYRIGHT: (C)2005,JPO&NCIPI

Abstract: The hybrid component (2), produced in an injection molding and jointer machine (1), has two metal sheets (3,4) and at least one plastics element (5) The metal sheets are assembled flat against each other between the mold sections (6,7), at least at the joint, and one metal sheet is distorted by the pressure of the molten plastics (K) into a button shape (17) The distortion penetrates (15) the second metal sheet forming a positive lock through an undercut The plastics hardens within the distorted shape

Abstract: In fabricating a transistor having the round corner recess channel structure, a buffer layer and a hard mask layer are formed in the active area of a semiconductor substrate. The buffer layer and the hard mask layer are etched so as to expose a predetermined channel region of the active area in the substrate. The predetermined channel region is wet etched to undercut the buffer layer below the hard mask layer. The exposed area of the substrate is etched by using the hard mask layer as an etching barrier so as to form a recess. The hard mask layer is removed. Light etch treatment is performed to round out the top corner of the recess. The buffer layer is then removed.

Abstract: A semiconductor device fabrication method applies a diazo novolac photoresist to a semiconductor wafer, followed by light exposure of its entire surface to form an underlying resist layer; forms a surface resist layer thereover; performs patterned-light exposure and heat treatment to the photoresist film consisting of the two resist layers formed; and exposes its entire surface to light, followed by development to process the photoresist film into a resist pattern, where the surface resist layer is in an inverse tapered shape, while the underlying resist layer is in an undercut shape relative to the surface resist layer.

Abstract: PROBLEM TO BE SOLVED: To provide a resin molding mold for injection molding which can obtain a resin product excellent in outer appearance quality. SOLUTION: The resin molding mold 1 includes a slide core 3 molding the resin product W with its end part Wb turned up in succession to a body part Wa, an outer mold 5, and an inclined core 7. The slide core 3 is moved perpendicularly to the mold opening direction A during mold opening, the outer surface Wd of the end part Wb of the resin product W is separated from the molding surface 5a of the outer mold 5, the movement of the outer mold 5 in the mold opening direction A is permitted, with the movement of the inclined core 7 in the mold opening direction A, it is moved by the amount of an undercut formed in the end part Wb, and the movement of the inclined core 7 in the mold opening direction A is made possible. The mold opening is obtained without spoiling the end part Wb to be the undercut part of the resin product W, a mold parting line PL is eliminated at a position corresponding to the outer surface Wc of the body part Wa of the resin product W which affects outer appearance quality, and the resin product W excellent in outer appearance quality is obtained. COPYRIGHT: (C)2007,JPO&INPIT

Abstract: In this paper, a very simple model of notching effect is reported. From an engineering point of view, the notching effect is an undercut between bottom of metal strip and stop layer (generally oxide) which can be observed in a Cl/sub 2/-BCl/sub 3/ metal etch when the geometry is shrunk. Starting from (Horwitz, 1993), a very detailed relation between geometrical decreasing , ion beam isotropy increasing, and sheath voltage was proposed. Then, a set of experiments performed on patterned aluminum wafers etched in a transformed coupled plasma (TCP) reactor were carried out in order to support the model based on sheath field curvature around metal lines. The experimental results are in good agreement with the theoretical predictions. This confirms the reliability of model proposed in order to manage the engineering problems which take place when a scaling down is performed.

Abstract: PROBLEM TO BE SOLVED: To mold a resin component to be exposed to undercut conditions while imparting a simple structure. SOLUTION: The resin component molding apparatus 40 has the first mold 43, a sliding block 44 and the second mold 45 which form a cavity space 50 for molding of a front fender 20 and a movement mechanism 60 moving the sliding block. The first mold 43 contains the doweling section 21 of the front fender 20 in undercut conditions. The sliding block 44 forms the first cavity space 51 for molding of the doweling section 21 between the sliding block and the first mold 43 and can move in such a direction as to separate relatively from the first mold 43. The movement mechanism 60 moves the sliding block 44 to the second point P2 where the front fender 20 follows the sliding block 44 to shrink so that the undercut conditions of the doweling section 21 with respect to the first mold 43 are canceled. COPYRIGHT: (C)2007,JPO&INPIT