Throughput and process control have always been critical

to the semiconductor device manufacturer. With the

advent of 300 mm wafers and dual process chambers,

new methods of control gas flow distribution have become

increasingly needed. 300 mm wafer processing often

requires tunable control of gas distribution across the

wafer to provide better process uniformity. Dual process

chambers require proper gas distribution for chamber

matching from single source gas panels.

The DELTA II flow ratio controller is the second generation

of MKS DELTA controllers enabling process gas flow ratio

control. The DELTA II has a wider dynamic ratio control

range and faster development of chamber flow while being

more adaptive to different tool and process conditions.

MKS has developed a unique patent pending ratio control

algorithm enabling ratio and flow response times of less

than two (2) seconds (See Figure 1). This control algorithm

also enables a twenty to one ratio control range, more

than double its industry leading predecessor. The DELTA

II maintains tight ratio control while input flow is changed

(See Figure 2). All this in a more compact package

with the additional features of web enabled setup and

diagnostics.

The DELTA II’s diagnostic feature allows the user to check

the DELTA’s performance in-situ, lowering costs through

reduced removal of “No Problem Found” devices. This

feature is enabled through a web browser utility accessed

through the device’s Ethernet port. This utility uses a

standard web browser – no special software is required.

For access, the IP address may be accessed through the

devices bright LED display.

Figure 1 — Ratio Response

The DELTA II ratio controller has a dynamic ratio range of up to 20:1 with

ratio response times under 2 seconds.

Figure 2 — Flow Response

The DELTA II ratio controller maintains ratio while input flow is changed.