Stamped circuit board

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A stamped circuit board (SCB) is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or traces etched from copper sheets laminated onto a non-conductive substrate. This technology is used for small circuits, for instance in the production of LEDs. [1]

Electronic component basic discrete device or physical entity in an electronic system used to affect electrons or their associated fields

An electronic component is any basic discrete device or physical entity in an electronic system used to affect electrons or their associated fields. Electronic components are mostly industrial products, available in a singular form and are not to be confused with electrical elements, which are conceptual abstractions representing idealized electronic components.

In electronics, a signal trace on a printed circuit board (PCB) is the equivalent of a wire for conducting signals. Each trace consists of a flat, narrow part of the copper foil that remains after etching. Signal traces are usually narrower than power or ground traces because the current carrying requirements are usually much less.

Light-emitting diode semiconductor light source

A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. This effect is called electroluminescence. The color of the light is determined by the energy required for electrons to cross the band gap of the semiconductor. White light is obtained by using multiple semiconductors or a layer of light-emitting phosphor on the semiconductor device.

Similar to printed circuit boards this layer structure may comprise glass-fibre reinforced epoxy resin and copper. Basically, in the case of LED substrates three variations are possible:

Printed circuit board board to support and connect electronic components

A printed circuit board (PCB) mechanically supports and electrically connects electronic components or electrical components using conductive tracks, pads and other features etched from one or more sheet layers of copper laminated onto and/or between sheet layers of a non-conductive substrate. Components are generally soldered onto the PCB to both electrically connect and mechanically fasten them to it.

  1. the PCB (printed circuit board),
  2. plastic-injection molding and
  3. the SCB.

Using the SCB technology it is possible to structure and laminate the most widely differing material combinations in a reel-to-reel production process. [2] As the layers are structured separately, improved design concepts are able to be implemented. Consequently, a far better and quicker heat dissipation from within the chip is achieved.

Production

Both the plastic and the metal are initially processed on separate reels, .i.e. in accordance with the requirements the materials are individually structured by stamping (“brought into form“) and then merged.

Advantages

The engineering respectively choice of substrates actually comes down to the particular application, module design/substrate assembly, material and thickness of the material involved.

Taking these parameters it is possible to attain a good thermal management by using SCB technology, because rapid heat dissipation from beneath the chip means a longer service life for the system. Furthermore, SCB technology allows the material to be chosen to correspond to the pertinent requirements and then to optimize the design to arrive at a “perfect fit”.

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Integrated circuit electronic circuit manufactured by lithography; set of electronic circuits on one small flat piece (or "chip") of semiconductor material, normally silicon

An integrated circuit or monolithic integrated circuit is a set of electronic circuits on one small flat piece of semiconductor material that is normally silicon. The integration of large numbers of tiny transistors into a small chip results in circuits that are orders of magnitude smaller, cheaper, and faster than those constructed of discrete electronic components. The IC's mass production capability, reliability and building-block approach to circuit design has ensured the rapid adoption of standardized ICs in place of designs using discrete transistors. ICs are now used in virtually all electronic equipment and have revolutionized the world of electronics. Computers, mobile phones, and other digital home appliances are now inextricable parts of the structure of modern societies, made possible by the small size and low cost of ICs.

CMOS technology for constructing integrated circuits

Complementary metal–oxide–semiconductor (CMOS) is a technology for constructing integrated circuits. CMOS technology is used in microprocessors, microcontrollers, static RAM, and other digital logic circuits. CMOS technology is also used for several analog circuits such as image sensors, data converters, and highly integrated transceivers for many types of communication. Frank Wanlass patented CMOS in 1963 while working for Fairchild Semiconductor.

Flexible electronics

Flexible electronics, also known as flex circuits, is a technology for assembling electronic circuits by mounting electronic devices on flexible plastic substrates, such as polyimide, PEEK or transparent conductive polyester film. Additionally, flex circuits can be screen printed silver circuits on polyester. Flexible electronic assemblies may be manufactured using identical components used for rigid printed circuit boards, allowing the board to conform to a desired shape, or to flex during its use. An alternative approach to flexible electronics suggests various etching techniques to thin down the traditional silicon substrate to few tens of micrometers to gain reasonable flexibility, referred to as flexible silicon.

Heat sink hardware component

A heat sink is a passive heat exchanger that transfers the heat generated by an electronic or a mechanical device to a fluid medium, often air or a liquid coolant, where it is dissipated away from the device, thereby allowing regulation of the device's temperature at optimal levels. In computers, heat sinks are used to cool central processing units or graphics processors. Heat sinks are used with high-power semiconductor devices such as power transistors and optoelectronics such as lasers and light emitting diodes (LEDs), where the heat dissipation ability of the component itself is insufficient to moderate its temperature.

Integrated circuit packaging

In electronics manufacturing, integrated circuit packaging is the final stage of semiconductor device fabrication, in which the block of semiconductor material is encapsulated in a supporting case that prevents physical damage and corrosion. The case, known as a "package", supports the electrical contacts which connect the device to a circuit board.

Computer cooling

Computer cooling is required to remove the waste heat produced by computer components, to keep components within permissible operating temperature limits. Components that are susceptible to temporary malfunction or permanent failure if overheated include integrated circuits such as central processing units (CPUs), chipset, graphics cards, and hard disk drives.

A via or VIA is an electrical connection between layers in a physical electronic circuit that goes through the plane of one or more adjacent layers. To ensure via robustness, IPC sponsored a round-robin exercise that developed a time to failure calculator.

The role of the substrate in power electronics is to provide the interconnections to form an electric circuit, and to cool the components. Compared to materials and techniques used in lower power microelectronics, these substrates must carry higher currents and provide a higher voltage isolation. They also must operate over a wide temperature range.

Quad Flat No-leads package

Flat no-leads packages such as quad-flat no-leads (QFN) and dual-flat no-leads (DFN) physically and electrically connect integrated circuits to printed circuit boards. Flat no-leads, also known as micro leadframe (MLF) and SON, is a surface-mount technology, one of several package technologies that connect ICs to the surfaces of PCBs without through-holes. Flat no-lead is a near chip scale plastic encapsulated package made with a planar copper lead frame substrate. Perimeter lands on the package bottom provide electrical connections to the PCB. Flat no-lead packages include an exposed thermal pad to improve heat transfer out of the IC. Heat transfer can be further facilitated by metal vias in the thermal pad. The QFN package is similar to the quad-flat package (QFP), and a ball grid array (BGA).

Electronic packaging is the design and production of enclosures for electronic devices ranging from individual semiconductor devices up to complete systems such as a mainframe computer. Packaging of an electronic system must consider protection from mechanical damage, cooling, radio frequency noise emission and electrostatic discharge. Product safety standards may dictate particular features of a consumer product, for example, external case temperature or grounding of exposed metal parts. Prototypes and industrial equipment made in small quantities may use standardized commercially available enclosures such as card cages or prefabricated boxes. Mass-market consumer devices may have highly specialized packaging to increase consumer appeal. Electronic packaging is a major discipline within the field of mechanical engineering.

Before getting to know phototool, the manufacture process of printed circuit board shall be introduced.

Thermal management of high-power LEDs

High power light-emitting diodes (LEDs) can use 350 milliwatts or more in a single LED. Most of the electricity in an LED becomes heat rather than light. If this heat is not removed, the LEDs run at high temperatures, which not only lowers their efficiency, but also makes the LED less reliable. Thus, thermal management of high power LEDs is a crucial area of research and development. It is necessary to limit the junction temperature to a value that will guarantee the desired LED lifetime.

Thermal copper pillar bump

The thermal copper pillar bump, also known as the "thermal bump", is a thermoelectric device made from thin-film thermoelectric material embedded in flip chip interconnects for use in electronics and optoelectronic packaging, including: flip chip packaging of CPU and GPU integrated circuits (chips), laser diodes, and semiconductor optical amplifiers (SOA). Unlike conventional solder bumps that provide an electrical path and a mechanical connection to the package, thermal bumps act as solid-state heat pumps and add thermal management functionality locally on the surface of a chip or to another electrical component. The diameter of a thermal bump is 238 μm and 60 μm high.

Microvias are used as the interconnects between layers in high density interconnect (HDI) substrates and printed circuit boards (PCBs) to accommodate the high input/output (I/O) density of advanced packages. Driven by portability and wireless communications, the electronics industry strives to produce affordable, light, and reliable products with increased functionality. At the electronic component level, this translates to components with increased I/Os with smaller footprint areas, and on the printed circuit board and package substrate level, to the use of high density interconnects (HDIs).

A molded interconnect device (MID) is an injection-molded thermoplastic part with integrated electronic circuit traces. The use of high temperature thermoplastics and their structured metallization opens a new dimension of circuit carrier design to the electronics industry. This technology combines plastic substrate/housing with circuitry into a single part by selective metallization.

A semiconductor package is a metal, plastic, glass, or ceramic casing containing one or more discrete semiconductor devices or integrated circuits. Individual components are fabricated on semiconductor wafers before being diced into die, tested, and packaged. The package provides a means for connecting the package to the external environment, such as printed circuit board, via leads such as lands, balls, or pins; and protection against threats such as mechanical impact, chemical contamination, and light exposure. Additionally, it helps dissipate heat produced by the device, with or without the aid of a heat spreader. There are thousands of package types in use. Some are defined by international, national, or industry standards, while others are particular to an individual manufacturer.

AlSiC, pronounced "alsick", is a metal matrix composite consisting of aluminium matrix with silicon carbide particles. It has high thermal conductivity, and its thermal expansion can be adjusted to match other materials, e.g. silicon and gallium arsenide chips and various ceramics. It is chiefly used in microelectronics as substrate for power semiconductor devices and high density multi-chip modules, where it aids with removal of waste heat.

Failure of electronic components Ways electronic elements fail and prevention measures

Electronic components have a wide range of failure modes. These can be classified in various ways, such as by time or cause. Failures can be caused by excess temperature, excess current or voltage, ionizing radiation, mechanical shock, stress or impact, and many other causes. In semiconductor devices, problems in the device package may cause failures due to contamination, mechanical stress of the device, or open or short circuits.

Co-fired ceramic

Co-fired ceramic devices are monolithic, ceramic microelectronic devices where the entire ceramic support structure and any conductive, resistive, and dielectric materials are fired in a kiln at the same time. Typical devices include capacitors, inductors, resistors, transformers, and hybrid circuits. The technology is also used for robust assembly and packaging of electronic components multi-layer packaging in the electronics industry, such as military electronics, MEMS, microprocessor and RF applications.

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