Die preparation

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Wafer glued on blue tape and cut into pieces, with some individual die removed Mounted wafer.jpg
Wafer glued on blue tape and cut into pieces, with some individual die removed

Die preparation is a step of semiconductor device fabrication during which a wafer is prepared for IC packaging and IC testing. The process of die preparation typically consists of two steps: wafer mounting and wafer dicing.

Wafer (electronics) thin slice of semiconductor material used in the fabrication of integrated circuits

In electronics, a wafer is a thin slice of semiconductor, such as a crystalline silicon (c-Si), used for the fabrication of integrated circuits and, in photovoltaics, to manufacture solar cells. The wafer serves as the substrate for microelectronic devices built in and upon the wafer. It and undergoes many microfabrication processes, such as doping, ion implantation, etching, thin-film deposition of various materials, and photolithographic patterning. Finally, the individual microcircuits are separated by wafer dicing and packaged as an integrated circuit.

Preparation (principle) management principle whereby people get ready for a final product or for a successful experience

Preparation is a management principle whereby people get ready for a final product or for a successful experience. Preparation means "a substance especially prepared". Preparation is a proceeding or readiness for a future event as a goal and an acceptable accomplished final outcome. It is to make something acceptable before you give it to others.

In the context of manufacturing integrated circuits, wafer dicing is the process by which die are separated from a wafer of semiconductor following the processing of the wafer. The dicing process can involve scribing and breaking, mechanical sawing or laser cutting. All methods are typically automated to ensure precision and accuracy. Following the dicing process the individual silicon chips are encapsulated into chip carriers which are then suitable for use in building electronic devices such as computers, etc.

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Wafer mounting

Wafer mounting is a step that is performed during the die preparation of a wafer as part of the process of semiconductor fabrication. During this step, the wafer is mounted on a plastic tape that is attached to a ring. Wafer mounting is performed right before the wafer is cut into separate dies. The adhesive film upon which the wafer is mounted ensures that the individual dies remain firmly in place during 'dicing', as the process of cutting the wafer is called.

Die (integrated circuit) an unpackaged integrated circuit

A die, in the context of integrated circuits, is a small block of semiconducting material on which a given functional circuit is fabricated. Typically, integrated circuits are produced in large batches on a single wafer of electronic-grade silicon (EGS) or other semiconductor through processes such as photolithography. The wafer is cut (diced) into many pieces, each containing one copy of the circuit. Each of these pieces is called a die.

The picture on the right shows a 300 mm wafer after it was mounted and diced. The blue plastic is the adhesive tape. The wafer is the round disc in the middle. In this case, a large number of dies were already removed.

Semiconductor-die cutting

In the manufacturing of micro-electronic devices, die cutting, dicing or singulation is a process of reducing a wafer containing multiple identical integrated circuits to individual dies each containing one of those circuits.

Integrated circuit electronic circuit manufactured by lithography; set of electronic circuits on one small flat piece (or "chip") of semiconductor material, normally silicon 639-1 ısoo

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.

During this process, a wafer with up to thousands of circuits is cut into rectangular pieces, each called a die. In between those functional parts of the circuits, a thin non-functional spacing is foreseen where a saw can safely cut the wafer without damaging the circuits. This spacing is called the scribe line or saw street. The width of the scribe is very small, typically around 100  μm. A very thin and accurate saw is therefore needed to cut the wafer into pieces. Usually the dicing is performed with a water-cooled circular saw with diamond-tipped teeth.

Micrometre one millionth of a metre

The micrometre or micrometer, also commonly known by the previous name micron, is an SI derived unit of length equalling 1×10−6 metre ; that is, one millionth of a metre.

Types of blades

The most common make up of blade used is either a metal or resin bond containing abrasive grit of natural or more commonly synthetic diamond, or borazon in various forms. Alternatively, the bond and grit may be applied as a coating to a metal former. See diamond tools.

Further reading

Related Research Articles

Semiconductor device fabrication process used to create the integrated circuits that are present in everyday electrical and electronic devices

Semiconductor device fabrication is the process used to create the integrated circuits that are present in everyday electrical and electronic devices. It is a multiple-step sequence of photolithographic and chemical processing steps during which electronic circuits are gradually created on a wafer made of pure semiconducting material. Silicon is almost always used, but various compound semiconductors are used for specialized applications.

In electronics design, tape-out or tapeout is the final result of the design process for integrated circuits or printed circuit boards before they are sent for manufacturing. The tapeout is specifically the point at which the graphic for the photomask of the circuit is sent to the fabrication facility. A synonym used at IBM is RIT. IBM differentiates between RIT-A for the non-metallic structures and RIT-B for the metal layers.

Flip chip, also known as controlled collapse chip connection or its abbreviation, C4, is a method for interconnecting semiconductor devices, such as IC chips and microelectromechanical systems (MEMS), to external circuitry with solder bumps that have been deposited onto the chip pads. The technique was developed by General Electric's Light Military Electronics Dept., Utica, N.Y. The solder bumps are deposited on the chip pads on the top side of the wafer during the final wafer processing step. In order to mount the chip to external circuitry, it is flipped over so that its top side faces down, and aligned so that its pads align with matching pads on the external circuit, and then the solder is reflowed to complete the interconnect. This is in contrast to wire bonding, in which the chip is mounted upright and wires are used to interconnect the chip pads to external circuitry.

Integrated circuit packaging Final stage of semiconductor device fabrication

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.

Wafer testing is a step performed during semiconductor device fabrication. During this step, performed before a wafer is sent to die preparation, all individual integrated circuits that are present on the wafer are tested for functional defects by applying special test patterns to them. The wafer testing is performed by a piece of test equipment called a wafer prober. The process of wafer testing can be referred to in several ways: Wafer Final Test (WFT), Electronic Die Sort (EDS) and Circuit Probe (CP) are probably the most common.

Boule (crystal) Synthetic ingot of crystal

A boule is a single crystal ingot produced by synthetic means.

Cleavage (crystal) tendency of crystalline materials to split along definite crystallographic structural planes

Cleavage, in mineralogy, is the tendency of crystalline materials to split along definite crystallographic structural planes. These planes of relative weakness are a result of the regular locations of atoms and ions in the crystal, which create smooth repeating surfaces that are visible both in the microscope and to the naked eye.

Microfabrication processes of fabrication of miniature structures

Microfabrication is the process of fabricating miniature structures of micrometre scales and smaller. Historically, the earliest microfabrication processes were used for integrated circuit fabrication, also known as "semiconductor manufacturing" or "semiconductor device fabrication". In the last two decades microelectromechanical systems (MEMS), microsystems, micromachines and their subfields, microfluidics/lab-on-a-chip, optical MEMS, RF MEMS, PowerMEMS, BioMEMS and their extension into nanoscale have re-used, adapted or extended microfabrication methods. Flat-panel displays and solar cells are also using similar techniques.

A dicing saw is a kind of saw which employs a high-speed spindle fitted with an extremely thin diamond blade or diamond wire to dice, cut, or groove semiconductor wafers, silicon, glass, ceramic, crystal, and many other types of material.

Disco Corporation

DISCO Corporation is a Japanese precision tools maker, especially for the semiconductor production industry.

The term die shrink refers to a simple semiconductor scaling of semiconductor devices, mainly transistors. The act of shrinking a die is to create a somewhat identical circuit using a more advanced fabrication process, usually involving an advance of lithographic node. This reduces overall costs for a chip company, as the absence of major architectural changes to the processor lowers research and development costs, while at the same time allowing more processor dies to be manufactured on the same piece of silicon wafer, resulting in less cost per product sold.

In microelectronics, a three-dimensional integrated circuit is an integrated circuit manufactured by stacking silicon wafers or dies and interconnecting them vertically using, for instance, through-silicon vias (TSVs) or Cu-Cu connections, so that they behave as a single device to achieve performance improvements at reduced power and smaller footprint than conventional two dimensional processes. 3D IC is just one of a host of 3D integration schemes that exploit the z-direction to achieve electrical performance benefits.

Wafer-level packaging

Wafer-level packaging (WLP) is the technology of packaging an integrated circuit while still part of the wafer, in contrast to the more conventional method of slicing the wafer into individual circuits (dice) and then packaging them. WLP is essentially a true chip-scale package (CSP) technology, since the resulting package is practically of the same size as the die. Wafer-level packaging allows integration of wafer fab, packaging, test, and burn-in at wafer level in order to streamline the manufacturing process undergone by a device from silicon start to customer shipment.

Wafer backgrinding is a semiconductor device fabrication step during which wafer thickness is reduced to allow stacking and high-density packaging of integrated circuits (IC).

Dicing tape is a backing tape used during wafer dicing, the cutting apart of pieces of semiconductor material following wafer microfabrication. The tape holds the pieces of semiconductor, known as dice, together during the cutting process, mounting them to a thin metal frame. The dice are removed from the dicing tape later on in the electronics manufacturing process.

Chip on board Circuit board manufacturing technique

Chip on board is the method of manufacturing where integrated circuits are wired and bonded directly to a printed circuit board. By eliminating the packaging of individual semiconductor devices, the completed product can be more compact, lighter, and less costly. In some cases chip on board construction improves the operation of radio frequency systems by reducing the inductance and capacitance of integrated circuit leads. Chip on board effectively merges two levels of electronic packaging, level 1 (components) and level 2, and may be referred to as a "level 1.5"