Abstract: An embodiment package on package (PoP) device includes a molding compound having a metal via embedded therein, a passivation layer disposed over the molding compound, the passivation layer including a passivation layer recess vertically aligned with the metal via, and a redistribution layer bond pad capping the metal via, a portion of the redistribution layer bond pad within the passivation layer recess projecting above a top surface of the molding compound.

Abstract: According to one embodiment, a flexible printed wiring board includes a base insulation layer, first wirings W1 on the base insulation layer, an intermediate insulation layer overlapped with the first wirings, connection pads on the intermediate insulation layer, a cover insulation layer overlapped with the connection pads and the intermediate insulation layer and including openings through which the connection pads are exposed to the cover layer, and conductive vias MT electrically connecting the first wirings to at least a part of the connection pads respectively. The conductive vias are overlapped with the connection pads in a thickness direction of the flexible printed wiring board.

Abstract: Methods and apparatus for solder connections. An apparatus includes a substrate having a conductive terminal on a surface; a passivation layer overlying the surface of the substrate and the conductive terminal; an opening in the passivation layer exposing a portion of the conductive terminal; at least one stud bump bonded to the conductive terminal in the opening and extending in a direction normal to the surface of the substrate; and a solder connection formed on the conductive terminal in the opening and enclosing the at least one stud bump. Methods for forming the solder connections are disclosed.

Abstract: A method and apparatus for multiple flexible circuit cable attachment is described herein. Gold bumps are bonded on interconnection pads of a substrate to create a columnar structure and solder or conductive epoxy is dispensed on the flexible cable circuit. The substrate and flexible cable circuit are aligned and pressed together using force or placement of a weight on either the substrate or flexible cable circuit. Appropriate heat is applied to reflow the solder or cure the epoxy. The solder wets to the substrate pads, assisted by the gold bumps, and have reduced bridging risk due to the columnar structure. A nonconductive underfill epoxy is applied to increase mechanical strength.

Abstract: A lead-free solder alloy contains zinc (Zn) as the main component and aluminum (Al) as an alloying metal. The solder alloy is a eutectic having a single melting point in the range of 320 to 390° C. (measured by DSC at a heating rate of 5° C. min-1).

Abstract: To enhance reliability of a test by suppressing defective bonding of a solder in the test of a semiconductor device, a method of manufacturing the semiconductor device includes: preparing a semiconductor wafer that includes a first pad electrode provided with a first cap film and a second pad electrode provided with a second cap film. Further, a polyimide layer that includes a first opening on the first pad electrode and a second opening on the second pad electrode is formed, and then, a rearrangement wiring that is connected to the second pad electrode via the second opening is formed. Next, an opening is formed in the polyimide layer such that an organic reaction layer remains on each of the first pad electrode and a bump land of the rearrangement wiring, then heat processing is performed on the semiconductor wafer, and then, a bump is formed on the rearrangement wiring.

Abstract: A substrate includes a support layer, a column-shaped first bump, and a second bump. The support layer has a main surface. The first bump is filled with a first conductive metal and also has a first upper surface and a side surface. The second bump includes a plurality of fine particles formed of a second conductive metal and also has a third portion configured to cover the first upper surface and a fourth portion configured to cover a part of the side surface. The first bump is disposed on the main surface, or the first bump is connected to an electrode disposed on the main surface. The second bump has a convex second upper surface. A height of the fourth portion in a direction perpendicular to the first upper surface is smaller than that of the first bump.

Abstract: Systems and methods for fabrication of a redistribution layer are described. There is no deposition of a seed layer, made from copper, on top of a substrate. The lack of the seed layer avoids a need for etching the seed layer. When the seed layer is not etched, the redistribution layer, also made from copper, is not etched.

Abstract: A plurality of high-k metal gate (HKMG) structures is formed over a substrate. The (HKMG) structures are separated by a plurality of gaps. The HKMG structures each include a first dielectric layer at an upper surface of the HKMG structure. The gaps are filled with a first conductive material. A portion of the first conductive material is removed in each of the gaps through an etching-back process. A metal oxide layer is formed using a spin-on deposition process. The metal oxide layer is formed over the (HKMG) structures and over the first conductive material. A second dielectric layer is formed over the metal oxide layer. An opening is etched in the second dielectric layer. The opening is etched through the second dielectric layer and through the metal oxide layer. The opening is filled with a second conductive material.

Abstract: An integrated circuit includes a substrate, a pad electrode disposed on the substrate, and a passivation layer disposed on the pad electrode and including an organic insulating material. The integrated circuit further includes a bump electrode disposed on the passivation layer and connected to the pad electrode through a contact hole. The passivation layer includes an insulating portion having a first thickness and covering an adjacent edge region of the pad electrode and the substrate, and a bump portion having a second thickness, that is greater than the first thickness, and covering a center portion of the pad electrode.

Abstract: A method of reducing electromagnetic interference in a semiconductor device includes: forming at least one functional circuit in a substrate of the semiconductor device; forming an integrated micro-shielding structure in the semiconductor device, the micro-shielding structure extending vertically through the substrate between a front surface and a back surface of the substrate and surrounding the functional circuit, the micro-shielding structure being configured to reduce radio frequency (RF) emissions in the semiconductor device and/or RF coupling between different functional parts of the functional circuit.

Abstract: The invention relates to a bump structure of a semiconductor device. An exemplary structure for a semiconductor device comprises a substrate; a contact pad over the substrate; a passivation layer extending over the substrate having an opening over the contact pad; and a conductive pillar over the opening of the passivation layer, wherein the conductive pillar comprises an upper portion substantially perpendicular to a surface of the substrate and a lower portion having tapered sidewalls.

Abstract: A semiconductor device and a method of manufacturing a semiconductor device. As a non-limiting example, various aspects of this disclosure provide a semiconductor package, and method of manufacturing thereof, that comprises a signal redistribution structure that comprises an anti-oxidation layer.

Abstract: A metal pillar with cushioned tip is disclosed. The cushioned tip offsets height difference among metal pillars. So that the height difference among metal pillars gives no significant effect to electrical coupling. The cushioned tip is a metal sponge. Additional one embodiment shows a second metal is plated on a tip of the metal sponge. A hardness of the second metal is greater than a hardness of a metal of the metal sponge, so that the second metal can stab into a corresponding metal sponge for electrical coupling.

Abstract: Educational information is provided to a user associated with a trigger object, and an education-related user attribute. Contemplated trigger objects include wearables, and especially pieces of jewelry. Contemplated education-related user attributes include current age, gender, subject being studied, current grade level, hobby, ethnicity, profession, vocation, location of interest, topic of interest, time period of interest, event of interest, favorite sport, favorite team, current school, color preference, resource preference, brand affinity, and expertise level. The educational information can be rendered directly on the trigger object, or on any other electronic rendering device.

Abstract: A semiconductor chip is provided including an integrated circuit on a substrate; pads electrically connected to the integrated circuit; a lower insulating structure defining contact holes exposing the pads, respectively; and first, second and third conductive patterns electrically connected to the pads. The second conductive pattern is between the first conductive pattern and the third conductive pattern when viewed from a plan view. Each of the first to third conductive patterns includes a contact portion filling the contact hole, a first conductive line portion extending in one direction on the lower insulating structure, and a bonding pad portion. Ends of the bonding pad portions of the first and third conductive patterns protrude in the one direction as compared with an end of the bonding pad portion of the second conductive pattern when viewed from a plan view.

Abstract: The present technology is directed to manufacturing semiconductor dies with under-bump metal (UBM) structures for die-to-die and/or package-to-package interconnects or other types of interconnects. In one embodiment, a method for forming under-bump metal (UBM) structures on a semiconductor die comprises constructing a UBM pillar by plating a first material onto first areas of a seed structure and depositing a second material over the first material. The first material has first electrical potential and the second material has a second electrical potential greater than the first electrical potential. The method further comprises reducing the difference in the electrical potential between the first material and the second material, and then removing second areas of the seed structure between the UBM pillars thereby forming UBM structures on the semiconductor die.

Abstract: Input/output pins for a chip-embedded substrate may be fabricated by applying a contact-distinct volume of solder to at least two contacts that are recessed within the chip-embedded substrate, temperature-cycling the chip-embedded substrate to induce solder reflow and define an input/output pin for each one of the at least two contacts, and machining the input/output pin for each one of the at least two contacts to extend exposed from the chip-embedded substrate to a common height within specification tolerance. Such a technique represents a paradigm shift in that the manufacturer of the chip-embedded substrate, as opposed to the immediate customer of the manufacturer, may assume the burden of quality control with respect to minimizing unintended solder void trapping under the input/output pins, thereby reinforcing existing customer loyalty and potentially attracting new customers.

Abstract: A method for redistribution layer routing is proposed. The method at least comprises inputting information regarding a redistribution layer layout, at least one netlist, and a constraint file. Next, it is creating a concentric-circle model based on the information, the netlist and the constraint file. Subsequently, it is assigning at least one pre-assignment net to at least one redistribution layer according to the concentric-circle model. Finally, the redistribution layer routing is performed.

Abstract: A method for packaging a microelectronic device in an hermetically sealed cavity and managing an atmosphere of the cavity with a dedicated hole, including making said cavity between a support and a cap layer such that a sacrificial material and the device are arranged in the cavity; removing the sacrificial material through at least one release hole, and hermetically sealing the release hole; making a portion of wettable material on the cap layer, around a blind hole or a part of said outside surface corresponding to a location of said dedicated hole; making a portion of fuse material on the portion of wettable material; making the dedicated hole by etching the cap layer; and reflowing the portion of fuse material with a controlled atmosphere, forming a bump of fuse material which hermetically plugs said dedicated hole.

Abstract: A redistribution circuit structure electrically connected to at least one conductor underneath is provided. The redistribution circuit structure includes a dielectric layer, an alignment, and a redistribution conductive layer. The dielectric layer covers the conductor and includes at least one contact opening for exposing the conductor. The alignment mark is disposed on the dielectric layer. The alignment mark includes a base portion on the dielectric layer and a protruding portion on the base portion, wherein a ratio of a maximum thickness of the protruding portion to a thickness of the base portion is smaller than 25%. The redistribution conductive layer is disposed on the dielectric layer. The redistribution conductive layer includes a conductive via, and the conductive via is electrically connected to the conductor through the contact opening. A method of fabricating the redistribution circuit structure and an integrated fan-out package are also provided.

Abstract: A wafer and a forming method thereof are provided. The wafer has a die region and a scribe-line region adjacent to the die region, and includes a conductive bonding pad in the die region of the wafer and a wafer acceptance test (WAT) pad in the scribe-line region of the wafer. A top surface of the WAT pad is lower than a top surface of the conductive bonding pad.

Abstract: To enhance reliability of a test by suppressing defective bonding of a solder in the test of a semiconductor device, a method of manufacturing the semiconductor device includes: preparing a semiconductor wafer that includes a first pad electrode provided with a first cap film and a second pad electrode provided with a second cap film. Further, a polyimide layer that includes a first opening on the first pad electrode and a second opening on the second pad electrode is formed, and then, a rearrangement wiring that is connected to the second pad electrode via the second opening is formed. Next, an opening is formed in the polyimide layer such that an organic reaction layer remains on each of the first pad electrode and a bump land of the rearrangement wiring, then heat processing is performed on the semiconductor wafer, and then, a bump is formed on the rearrangement wiring.

Abstract: A multi-layer semiconductor device includes a first semiconductor structure having first and second opposing surfaces, the second surface of the first semiconductor structure having at least a first semiconductor package pitch. The multi-layer semiconductor device also includes a second semiconductor structure having first and second opposing surfaces, the first surface of the second semiconductor structure having a second semiconductor package pitch. The multi-layer semiconductor device additionally includes a third semiconductor structure having first and second opposing surfaces, the first surface of the third semiconductor structure having a third semiconductor package pitch which is different from at least the second semiconductor package pitch. The second and third semiconductor structures are provided on a same package level of the multi-layer semiconductor device. A corresponding method for fabricating a multi-layer semiconductor device is also provided.

Abstract: Provided are liquid crystal display and the method for manufacturing the same. According to an aspect of the present disclosure, there is provided a liquid crystal display device, including: a first substrate; a gate electrode disposed on the first substrate; a semiconductor pattern layer disposed on the gate electrode; and a source electrode and a drain electrode disposed on the semiconductor pattern layer and facing each other, wherein the gate electrode includes a reference plane and a protrusion protruding from the reference plane in a horizontal direction, and the protrusion overlaps the source electrode and the drain electrode.

Abstract: An image sensor having a lower device, an upper devise, and a TSV structure is provides. The lower device may include a lower substrate, a lower TSV pad, and a lower interlayer insulating layer. The lower TSV pad may be formed over the lower substrate. The lower interlayer insulating layer may cover the lower TSV pad. The upper device may include an upper substrate, an upper TSV pad, and an upper interlayer insulating layer. The upper TSV pad may be formed over the upper substrate. The upper interlayer insulating layer may cover the upper TSV pad. The TSV structure may vertically pass through the upper device and electrically connect the upper TSV pad to the lower TSV pad. The upper TSV pad may include an upper opening. The lower TSV pad may include a unit pad and a lower opening. The unit pad may be exposed through the upper opening and contacts the TSV structure in a top view.

Abstract: Methods and apparatus are disclosed for manufacturing metal contacts under ground-up contact pads within a device. A device may comprise a bottom metal layer with a bottom metal contact, a top metal layer with a top metal contact, and a plurality of middle metal layers. Any given metal layer of the plurality of middle metal layers comprises a metal contact, the metal contact is substantially vertically below the top metal contact, substantially vertically above the bottom metal contact, and substantially vertically above a metal contact in any metal layer that is below the given metal layer. The metal contacts may be of various and different shapes. All the metal contacts in the plurality of middle metal layers and the bottom metal contact may be smaller than the top metal contact, therefore occupying less area and saving more area for other functions such as device routing.

Abstract: A method of combinatorial masking employs a combinatorial etch mask that includes a top layer of a stack of material layers and a secondary mask on the top layer to etch other material layers of the stack. The method includes patterning a first layer at a top of the stack of material layers, and providing the secondary mask on top of the patterned first layer. The method further includes etching other material layers of the stack including a second layer below the first layer with the combinatorial mask and then etching the first layer along with the other material layers of the stack excluding the second layer using the secondary mask as an etch mask.

Abstract: The invention relates to the manufacturing process of a solar cell (1) with back contact and passivated emitter, comprising a dielectric stack (10) of at least two layers consisting of at least a first dielectric layer (11) made of AlOx in contact with a p-type silicon layer (3), and a second dielectric layer (13) deposited on the first dielectric layer (11). Besides, the method of manufacturing comprising a formation step of at least one partial opening (15) preferably by laser ablation into the dielectric stack (10), sparing at least partially the aforementioned first dielectric layer.

Abstract: A method of manufacturing a semiconductor device includes: forming a ridge on a semiconductor layer stacked on a substrate by removing a part of the semiconductor layer; forming an electrode on the ridge so as to have a flat portion having a flat surface substantially parallel to the upper surface of the ridge and sloped portions on both sides of the flat portion with each of the sloped portions having a sloped surface that is sloped with respect to the upper surface of the ridge; forming a protective film disposed on each side of the ridge to cover a region from the side surface of the ridge to the sloped surface of the sloped portion of the electrode; and forming a pad electrode at least on an upper surface of the electrode and the protective film.

Abstract: A structure comprises a post passivation interconnect layer formed over a semiconductor substrate, a metal bump formed over the post passivation interconnect layer and a molding compound layer formed over the semiconductor substrate. A lower portion of the metal bump is embedded in the molding compound layer and a middle portion of the metal bump is surrounded by a concave meniscus molding compound protection layer.

Abstract: Object is to prevent a coupling failure between a rewiring and a coupling member for coupling to outside. A passivation film and a first polyimide film are formed so as to cover a wiring layer. A first opening portion is formed in the first polyimide film. A rewiring is formed on the first polyimide film so as to be coupled to the wiring layer via the first opening portion. A second polyimide film that covers the rewiring and has a second opening portion communicated with the rewiring is formed. A palladium film is formed as a barrier film by sputtering on a portion of the surface of the rewiring at which the second opening portion exists. A solder ball is coupled to the palladium film.

Abstract: Pass-through 3D interconnects and microelectronic dies and systems of stacked dies that include such interconnects to disable electrical connections are disclosed herein. In one embodiment, a system of stacked dies includes a first microelectronic die having a backside, an interconnect extending through the first die to the backside, an integrated circuit electrically coupled to the interconnect, and a first electrostatic discharge (ESD) device electrically isolated from the interconnect. A second microelectronic die has a front side coupled to the backside of the first die, a metal contact at the front side electrically coupled to the interconnect, and a second ESD device electrically coupled to the metal contact. In another embodiment, the first die further includes a substrate carrying the integrated circuit and the first ESD device, and the interconnect is positioned in the substrate to disable an electrical connection between the first ESD device and the interconnect.

Abstract: Methods of forming connector pad structures, interconnect structures, and structures thereof are disclosed. In some embodiments, a method of forming a connector pad structure includes forming an underball metallization (UBM) pad, and increasing a surface roughness of the UBM pad by exposing the UBM pad to a plasma treatment. A polymer material is formed over a first portion of the UBM pad, leaving a second portion of the UBM pad exposed.

Abstract: Provided is a package structure including a circuit board, a plurality of first contact pads, a plurality of metal pillars and at least one chip. The first contact pads are disposed on the circuit board. The chip is disposed on one portion of the first contact pads. The metal pillars are disposed on the other portion of the first contact pads, where the chip is surrounded by the metal pillars. A method for manufacturing the package structure is also provided.

Abstract: In various embodiments, a method for processing a wafer may include: providing a wafer having at least one die region and at least one metallization disposed over the at least one die region; covering the at least one metallization with a protecting layer; plasma etching the wafer to form at least one die.

Abstract: A plurality of semiconductor devices provided on a silicon carbide substrate are provided with electrode layers, respectively. The silicon carbide substrate is cut at a region of an exposed surface of the silicon carbide substrate that separates the electrode layers to individually separate the semiconductor devices. A stress relaxation resin is applied to each individually separated semiconductor device to cover the exposed surface at a peripheral end portion of that surface of the semiconductor device which has the electrode layer thereon. A semiconductor apparatus can thus be obtained that also allows a semiconductor device with a silicon carbide or similar compound semiconductor substrate to adhere to a sealant resin via large adhesive strength and thus allows the sealant resin to be less crackable, less peelable and the like by thermal stress caused in operation.

Abstract: A pad structure for a complementary metal-oxide-semiconductor (CMOS) image sensor is provided. A semiconductor substrate is arranged over a back end of line (BEOL) metallization stack, and comprises a scribe line opening. A buffer layer lines the scribe line opening. A conductive pad comprises a base region and a protruding region. The base region is arranged over the buffer layer in the scribe line opening, and the protruding region protrudes from the base region into the BEOL metallization stack. A dielectric layer fills the scribe line opening over the conductive pad, and is substantially flush with an upper surface of the semiconductor substrate. Further, a method for manufacturing the pad structure, as well as the CMOS image sensor, are provided.

Abstract: Methods and apparatus for solder connections. An apparatus includes a substrate having a conductive terminal on a surface; a passivation layer overlying the surface of the substrate and the conductive terminal; an opening in the passivation layer exposing a portion of the conductive terminal; at least one stud bump bonded to the conductive terminal in the opening and extending in a direction normal to the surface of the substrate; and a solder connection formed on the conductive terminal in the opening and enclosing the at least one stud bump. Methods for forming the solder connections are disclosed.

Abstract: Even when a stiffener is omitted, the semiconductor device which can prevent the generation of twist and distortion of a wiring substrate is obtained. As for a semiconductor device which has a wiring substrate, a semiconductor chip by which the flip chip bond was made to the wiring substrate, and a heat spreader adhered to the back surface of the semiconductor chip, and which omitted the stiffener for reinforcing a wiring substrate and maintaining the surface smoothness of a heat spreader, a wiring substrate has a plurality of insulating substrates in which a through hole whose diameter differs, respectively was formed, and each insulating substrate contains a glass cloth.

Abstract: A device comprises a top package mounted on a bottom package through a joint structure, wherein the joint structure comprises a solder ball of the top package coupled to a metal structure embedded in the bottom package and an epoxy protection layer having a first edge in direct contact with a top surface of the bottom package and a second edge surrounding a lower portion of the solder ball.

Abstract: A system and method for preventing cracks in a passivation layer is provided. In an embodiment a contact pad has a first diameter and an opening through the passivation layer has a second diameter, wherein the first diameter is greater than the second diameter by a first distance of about 10 ?m. In another embodiment, an underbump metallization is formed through the opening, and the underbump metallization has a third diameter that is greater than the first diameter by a second distance of about 5 ?m. In yet another embodiment, a sum of the first distance and the second distance is greater than about 15 ?m.

Abstract: A semiconductor device has integrated passive circuit elements. A first substrate is formed on a backside of the semiconductor device. The passive circuit element is formed over the insulating layer. The passive circuit element can be an inductor, capacitor, or resistor. A passivation layer is formed over the passive circuit element. A carrier is attached to the passivation layer. The first substrate is removed. A non-silicon substrate is formed over the insulating layer on the backside of the semiconductor device. The non-silicon substrate is made with glass, molding compound, epoxy, polymer, or polymer composite. An adhesive layer is formed between the non-silicon substrate and insulating layer. A via is formed between the insulating layer and first passivation layer. The carrier is removed. An under bump metallization is formed over the passivation layer in electrical contact with the passive circuit element. A solder bump is formed on the under bump metallization.

Abstract: Even when a stiffener is omitted, the semiconductor device which can prevent the generation of twist and distortion of a wiring substrate is obtained. As for a semiconductor device which has a wiring substrate, a semiconductor chip by which the flip chip bond was made to the wiring substrate, and a heat spreader adhered to the back surface of the semiconductor chip, and which omitted the stiffener for reinforcing a wiring substrate and maintaining the surface smoothness of a heat spreader, a wiring substrate has a plurality of insulating substrates in which a through hole whose diameter differs, respectively was formed, and each insulating substrate contains a glass cloth.

Abstract: A metal bump structure for use in a driver IC includes a passivation layer disposed on a metal pad and defining a recess on the metal pad, an adhesion layer in said recess, on the metal pad and on the passivation layer, a metal bump disposed in the recess and completely covering the adhesion layer, and a capping layer disposed on the metal bump and completely covering the metal bump so that the metal bump is not exposed to an ambient atmosphere.

Abstract: A semiconductor device includes: a first semiconductor layer of a nitride semiconductor formed on a substrate; a second semiconductor layer of a nitride semiconductor formed on the first semiconductor layer; and a gate electrode, a source electrode, a drain electrode, and a hole extraction electrode, each of which is formed on the second semiconductor layer, wherein between the source electrode and the hole extraction electrode or in a region right under the source electrode, the first semiconductor layer and the second semiconductor layer form a vertical interface approximately perpendicular to a surface of the substrate, and a surface of the first semiconductor layer configured to form the vertical interface is an N-polar surface.

Abstract: The present disclosure provides a method for manufacturing a semiconductor package. The method includes (1) determining a die warpage value under a predetermined temperature range; (2) determining a difference between a density of a top metal and a density of a bottom metal of a substrate according to the die warpage value; and (3) joining the die and the substrate under the predetermined temperature range. The top metal includes all metal layers overlying a middle layer, and the bottom metal includes all metal layers underlying the middle layer. The middle layer includes a core or a metal layer.

Abstract: Wafer-level package (semiconductor) devices are described that have a reinforcement layer formed on an adhesion layer and/or a semiconductor substrate and covering at least a portion of at least one solder bump. Additionally, the reinforcement layer may cover at least a portion of a semiconductor device (e.g., a die) mounted on the semiconductor substrate. In an implementation, the wafer-level package (semiconductor) device may include an integrated circuit chip with an attached die, where the integrated circuit chip has at least one solder bump formed thereon with a reinforcement layer formed on a surface of the integrated circuit chip, where the reinforcement layer embeds the die and covers a portion of the at least one solder bump.

Abstract: The invention is to provide a structure of IC pad and its forming method. The structure is arranged in an insulation layer and is comprised of a lower electric-conduction layer, a compound layer structure and a pad layer. The lower electric-conduction layer is arranged at an appropriate position in the insulation layer and is connected to an electric potential. The compound layer structure is arranged on the insulation layer and is composed of at least one electric-conduction layer and at least one electric-conduction connecting layer, both are inter-overlapped to each other. The pad layer is arranged on the compound layer structure.

Abstract: The invention is to provide a structure of IC pad and its forming method. The structure is arranged in an insulation layer and is comprised of a lower electric-conduction layer, a compound layer structure and a pad layer. The lower electric-conduction layer is arranged at an appropriate position in the insulation layer and is connected to an electric potential. The compound layer structure is arranged on the insulation layer and is composed of at least one electric-conduction layer and at least one electric-conduction connecting layer, both are inter-overlapped to each other. The pad layer is arranged on the compound layer structure.