pins. In the 'old days' (1970s), wires were attached by hand, but now specialized machines perform the task. Traditionally, these wires have been composed of gold, leading to a lead frame (pronounced "leed frame") of solder-plated copper; lead is poisonous, so lead-free "lead frames" are now mandated by RoHS. Chip scale package (CSP) is another packaging technology. A plastic dual in-line package, like most packages, is many times larger than the actual die hidden inside, whereas CSP chips are nearly the size of the die; a CSP can be constructed for each die before the wafer is diced. The packaged chips are retested to ensure that they were not damaged during packaging and that the die-to-pin interconnect operation was performed correctly. A laser then etches the chip's name and numbers on the package. Hazardous materials Many toxic materials are used in the fabrication process. These include: poisonous elemental dopants, such as arsenic, antimony, and phosphorus. poisonous compounds, such as arsine, phosphine, tungsten hexafluoride and silane. highly reactive liquids, such as hydrogen peroxide, fuming nitric acid, sulfuric acid, and hydrofluoric acid. It is vital that workers should not be directly exposed to these dangerous substances. The high degree of automation common in the IC fabrication industry helps to reduce the risks of exposure. Most fabrication facilities employ exhaust management systems, such as wet scrubbers, combustors, heated absorber cartridges, etc., to control the risk to workers and to the environment. Timeline of commercial MOSFET nodes See also Deathnium Glossary of microelectronics manufacturing terms List of semiconductor scale examples MOSFET CMOS Multigate device FinFET Semiconductor industry Foundry model Semiconductor equipment sales leaders by year International Technology Roadmap for Semiconductors Semiconductor consolidation Local oxidation of silicon (LOCOS) List of integrated circuit manufacturers List of semiconductor fabrication plants Microfabrication Semiconductor Equipment and Materials International (SEMI) — the semiconductor industry trade association SEMI font for labels on wafers Etch pit density Passivation Planar process Transistor count References Further reading , section 14.2. Wiki related to Chip Technology External links Semiconductor glossary Wafer heating Designing a Heated Chuck for Semiconductor Processing Equipment Cleanroom technology MOSFETs