Polysilicon for silicon wafers originates from metallurgical-grade silicon extracted from quartz sand, the U.S. Department of Energy explainsCITE:E1. The Department of Energy describes polysilicon manufacturing methods that rely on highly reactive gases, synthesized primarily from metallurgical-grade silicon obtained from quartz sand together with hydrogen and chlorineCITE:E1. SUMCO Corporation states that once purified to no more than a few parts per billion of metal impurities, the polysilicon feedstock is loaded into a quartz crucible along with boron and phosphorous and melted at a temperature of around 1420°CCITE:E2. Shin-Etsu Chemical specifies that the polycrystalline silicon it uses as feedstock reaches a purity of 99.999999999%CITE:E4.
SUMCO Corporation grows monocrystalline ingots by placing a seed crystal silicon rod on the surface of the molten silicon and pulling it upward while rotating itCITE:E3. This forms a monocrystalline ingot that shares the same atomic orientation as the seed crystalCITE:E3. Shin-Etsu Chemical states that the resulting crystals can reach 300mm in diameter and grow longer than one meterCITE:E5.
SUMCO Corporation cuts the grown ingot into slices of around 1mm thickness using an inner-diameter saw or wire saw to form the wafersCITE:E6.
SUMCO Corporation polishes wafer surfaces through mechano-chemical polishing with colloidal silica, making the surfaces perfectly flat and giving them a mirror finishCITE:E7.
| Stage | Parameter | Value | Source |
|---|---|---|---|
| Feedstock purification | Polysilicon purity | 99.999999999% | CITE:E4 |
| Melting | Furnace temperature | ~1420°C | CITE:E2 |
| Crystal growth | Ingot diameter | Up to 300mm | CITE:E5 |
| Crystal growth | Ingot length | Over 1 meter | CITE:E5 |
| Slicing | Wafer thickness | ~1mm | CITE:E6 |
Read in sequence, the documented figures describe one continuous chain of tightening tolerances: quartz sand is reduced to metallurgical-grade silicon, refined into polysilicon at 99.999999999% purity, melted at around 1420°C, pulled into ingots up to 300mm in diameter and over one meter long, sliced into wafers roughly 1mm thick, and finished with colloidal-silica polishing to a mirror surface. SUMCO Corporation and Shin-Etsu Chemical, describing separate stages of this chain on their own process pages, both point to 300mm-class ingots as the current benchmark, and the U.S. Department of Energy's account of polysilicon's quartz-sand origin lines up with the purity and melting figures SUMCO and Shin-Etsu report for the same feedstock.
Polysilicon for silicon wafers originates from metallurgical-grade silicon extracted from quartz sand, the U.S. Department of Energy explainsCITE:E1.
SUMCO Corporation grows monocrystalline ingots by placing a seed crystal silicon rod on the surface of the molten silicon and pulling it upward while rotating i…
SUMCO Corporation cuts the grown ingot into slices of around 1mm thickness using an inner-diameter saw or wire saw to form the wafersCITE:E6.
SUMCO Corporation polishes wafer surfaces through mechano-chemical polishing with colloidal silica, making the surfaces perfectly flat and giving them a mirror …
The eleven-nines purity spec (99.999999999%) that Shin-Etsu cites for its polysilicon feedstock is the number that makes everything downstream possible: melting at around 1420°C leaves no room for metallic contamination to disrupt the atomic ordering that seed-pulling crystal growth depends on. Reading the four stages in sequence shows how little margin for error there is at each step — a 300mm, meter-long ingot sliced into roughly 1mm wafers and then polished with colloidal silica to a mirror finish is a process where a defect introduced during melting cannot be fixed by later polishing. For anyone tracking capacity in this supply chain, the metric worth watching is ingot diameter: 300mm is the figure both SUMCO and Shin-Etsu describe as current practice, and any move beyond it would mark a new wafer-size transition.
Google announced a €13 billion ($15.1 billion) investment in Finnish AI infrastructure to be deployed in 2027–2028, its largest single investment in Europe. The plan covers new data centers in Kajaani, Muhos, and Vaala plus an expansion in Hamina, backed by a 22-year power deal for 50% of Loviisa nuclear plant output and projected to support 37,000 construction-phase jobs and 7,000 permanent roles.
Chenbro (勤誠, 8210) reported August 2026 revenue of NT$2.457 billion, roughly flat month-on-month (-0.2%) but up 40.5% from a year earlier. Cumulative January–August revenue reached NT$19.848 billion, up 51.7% year-on-year.
Chang Hwa Bank (TWSE: 2801) reported cumulative after-tax profit of NT$15.567 billion for January through August, up 23.21% year-on-year with EPS of NT$1.29, a record for the period. The bank attributed the gain to loan, deposit, and wealth management momentum, and August alone delivered NT$2.916 billion in profit, up 29.16% year-on-year.