Silicon Wafer Specials
Bare Silicon Wafers
- Silicon Wafers from All Major Suppliers
– Komatsu Electronic Metals Co., Ltd
– LG Siltron
– MEMC Electronic Materials Inc.
– Shin-Etsu Handotai, Ltd (SEH)
– Siltronic AG
– Sumitomo Mitsubishi Silicon Group (SUMCO USA)
– Toshiba Ceramics Co. Ltd.
- Select from All Grades of Silicon Wafers
– Prime, Device Grade, Litho and Furnace Grade wafers
– Low Particle Test Monitor wafers
– Low Cost, Mechanical Grade Wafers
– Reclaim, Solar Grade Wafers and Scrap
- Wide Variety of Silicon Wafer Types
– Czochralski (CZ) grown silicon monocrystal
– Float Zone (FZ) grown silicon monocrystal
– Epitaxial silicon
– Silicon on Insulator (SOI)
– 300mm and 200mm Silicon wafers available in stock
– Other diameters available on request
Silicon Wafer Applications
Silicon Wafer Specifications
Silicon wafers larger than 150mm are classified into two categories:
Industry standards for silicon Mechanical Test Wafers and Process Test Wafers are reported in the following SEMI Standards:
- Mechanical Test Wafers
- Process Test Wafers
These standards specify dimensional and crystallographic orientation characteristics and limits on surface defects of silicon substrates.
- SEMI Standard M1-1105, Specifications for Polished Monocrystalline Silicon Wafers
- SEMI M1.15, Standard for 300mm Polished Monocrystalline Silicon Wafers (Notched) specifies 300mm silicon wafer attributes.
- SEMI M1.9, Standard for 200mm Polished Monocrystalline Silicon Wafers (Notched) specifies 200mm silicon wafer attributes.
- SEMI Standard M8-0306, Specifications for Polished Monocrystalline Silicon Wafers
- SEMI Standard M24-1105, Specification for Polished Monocrystalline Silicon Premium Wafers
Mechanical Test Grade Silicon Wafers
Silicon Mechanical Test Wafers are silicon wafers suitable for testing equipment with emphasis on dimensional and structural characteristics only.
Mechanical grade silicon wafers are commonly used to perform equipment automation handling tests, reliability marathons, and software tests.
Mechanical test wafers are also used to assess interoperability performance of wafer handling hardware.
By using silicon test wafers on automation hardware, equipment manufacturers can simulate the behavior of silicon wafers used by fab end users.
Mechanical grade silicon wafers can be used for some process development applications that are not sensitive to particulates and surface defects.
Click here for Mechanical Grade Silicon Wafers: 300mm Mechanical Grade Silicon Wafers
Process Test Grade Silicon Wafers
Silicon Process Test Wafers are silicon wafers suitable for process monitoring as well as some processing applications in semiconductor fabrication.
Silicon Process Test wafers are also known as Monitor Wafers. Monitor wafers can be used to assess equipment cleanliness and support particle measurement.
They can also be used to evaluate metallic contamination.
Semiconductor capital equipment manufacturers also use process test silicon wafers to perform development and characterization of semiconductor fabrication processes.
Films, such as dielectrics and metals, can be deposited on these silicon wafers.
Some equipment manufacturers study the silicon wafers afterwards to assess the integrity of the films and the uniformity of deposition.
Others may study rates of material removal from the silicon wafers, or contamination effects resulting from subsequent fabrication processes.
Silicon wafers may also be patterned using photoresist and advanced photolithography techniques.
Photoresist is a special, light sensitive chemical which is applied evenly across the surface of the silicon wafer.
Light is transmitted through a stencil-like pattern, called a photomask.
Exposing the photoresist to light leaves a pattern on the silicon wafer, which is used to build complex structures.
Click here for more information on Patterned Test Wafers: Patterned Test Wafers
Within the Process Test Wafer category of Silicon Wafers, there are three additional classifications of Premium Wafers, designated for specific process applications.
Premium silicon wafers have tighter specification values in particular attributes, and looser specification values for others.
The three types of Premium Wafers are Particle Grade, Furnace Grade and Lithography Grade.
Particle Grade Silicon Wafers
Particle Grade Process Test Wafers, also known as Particle Test Monitors, are silicon wafers designed for particle measurement applications.
Per SEMI specification, Particle Test Monitors for 250nm Design Rule Usage must have less than 0.6 particles of greater than 0.125μm per square centimeter and less than 0.15 particles of greater than 0.25μm per square centimeter.
For 130nm Design Rule Usage, 300mm wafers must have ≤60 Localized Light Scatters (LLS) at greater than or equal to 90nm.
Click here for more information on Premium Low Particle and Low Haze Test Wafers:Premium Low Particle Test Wafers andPremium Low Haze Test Wafers
Furnace Grade Silicon Wafers
Furnace Grade Test Wafers are silicon wafers with less stringent requirements for particle performance, but more aggressive requirements for electrical and chemical characteristics.
Resistivity of Furnace Grade wafers must be greater than or equal to 1Ω-cm. Carrier Recombination Lifetime must be ≥200μs.
Furnace Grade Silicon Wafers also have tighter specifications than ordinary silicon wafers for oxygen, carbon and metal concentration.
Photolithography Grade Silicon Wafers
Lithography and Patterning Grade Process Test Wafers differ from ordinary silicon wafers in their requirements for thickness variation, warp and site flatness.
For 250nm Design Rule Usage, SEMI Standard M24 requires Flatness per Site (SFSR) of ≤ 0.2μm at site size 25 x 25mm (Percent Usable Area, PUA: 90%).
For 130nm Design Rule Usage, Flatness per Site (SFSR) of ≤ 130nm for site size 25 x 32mm (PUA 90%) is required.
Virgin Silicon Wafers
Virgin silicon test wafers are mechanical or process test wafers that have not previously been used in semiconductor manufacturing.
Virgin silicon wafers are distinguished from Reclaimed Silicon Wafers, which have been processed to remove previously deposited films or materials.
Solar Grade Silicon
Scrap from silicon wafers used in the semiconductor industry can be reused as raw material for silicon in the solar, photovoltaic device industry.
Follow this link for more information on solar grade silicon wafers: Solar Grade Wafers