Technical Support Services

An Ultra-Pure Water Plant with an overall capacity of 75/180 gpm (~17/40 m³/hr) delivers high purity water to the Fab of SCL.  Three on-site deep bore wells cater to the Raw Water requirements.

The Ultra-Pure Water Plant designed as per industry standards, employs Reverse Osmosis (RO) and Ion exchange processes. Raw water is first treated through the Double Pass RO unit having configuration of 3:2:1 array for primary RO and 2:1 array for Secondary RO unit. Permeate from RO is passed through Ion Exchange Mixed Bed units. The product water is filtered thereafter through 0.04 micron absolute charged filters before delivering into the supply loop.

Combination of UV sterilization units (254 nm & 185 nm wave length) are installed in the plant to control TOC levels. At all critical points, on-line analyzers such as Conductivity, Resistivity analyzers, Silica analyzer, TOC analyzers, Particulate Monitor etc. are installed to ensure desired quality levels.

Performance of RO Units, Ion Exchange beds etc. is ensured by following strict maintenance regimen in line with the recommended practices for such high purity plants.

The high purity Water Distribution Loop comprising of PVDF headers and Sub-headers is designed to maintain 5-7 fps velocity at all the points. The return line of the loop terminates into high purity water storage tank which is provided with N₂ blanket to maintain purity levels.

Ultra-Pure water Specifications:

RESISTIVITY

18.0 Mohm-cm

SILICA

<   3 ppb

TOC

< 20 ppb

PARTICLES

0.2 µ size

< 10 per Ltrs.

Gas and Chemical Management Systems

Nitrogen

A high purity Nitrogen gas plant supplying upto 400 Nm³/hr of general purity N₂ gas with associated liquid back up storage plant is available on site. Regenerable purifier of 60 Nm³/hr capacity further purifies the gas from the plant for supply to specific process equipment in the Fab.

Quality Specifications of N₂ gas

Impurity

O₂

< 0.2

H₂O

< 0.2

THC

< 0.2

CO + CO₂

< 0.2

< 10/ ft³

Oxygen

A Cryo Storage tank of 5000 litre capacity supplies oxygen at 20 Nm³/hr through regenerable purifiers to the Fab.  On-line analyzers at the purifier and at the point-of-use monitor the purity levels of the gas.

        Quality Specifications of O₂ gas

         Impurity

    (ppm)

     N₂

    < 0.5

     H₂O

    < 0.1

     THC

    < 0.1

     CO + CO₂

    < 0.2

     Particle ≥ 0.2µ

    < 10/ ft³

Hydrogen

Hydrogen gas is supplied to the wafer Fab from the 6 x 6 cylinders manifold.  The gas is purified through a non-regenerable purifier (6 nm³/hr capacity) and monitored through analyzers to ensure quality levels.

Quality Specifications of H₂ gas

Impurity

Level

(ppm)

O₂       

< 0.2

H₂O

< 0.1

< 0.1

< 0.4

Particle ≥ 0.2µ

< 10/ ft³

Gas Distribution system for N_2, O_2, and H₂ is through Stainless Steel 316L electro-polished pipelines
having surface finish of <10µ inches Ra.

Speciality Gases

Speciality Gases (16 nos) are stored and distributed from high-tech gas storage cabinets
through valve manifold boxes (VMBs) and co-axial stainless 316L electro-polished tubing.
Central monitoring system with an extensive gas detection infrastructure is installed
to ensure safe operations.

Chemicals

Chemicals are stored in a well ventilated room away from the main manufacturing area. 
A chemical mix room abutting the Clean Room is used for decanting chemicals from bottles
from where they are hand-carried to individual process equipment.