B2 - Schoonover, Inc.

Thin Film Deposition Controllers and Monitors
Sentinel ® III Thin Film Deposition Controller
Sentinel ® III Thin Film Deposition Controller
The system can independently control simultaneous evaporation of
elements from two separate sources as well as sequential evaporation of
two elements with interfacial alloying between layers. Operators can also
measure evaporation rates of two elements from one source while
controlling the source power.
Sentinel ¨ III can measure and control single-element depositions in
continuous or batch operations while monitoring the level of background
gas. In addition, it can measure the evaporation rate of fractionated
elements from certain compounds and can even reject cross-channel
interference in binary-alloy depositions.
Sentinel¨ III is designed to meet demanding vacuum-deposition
requirements. Using advanced Electron Impact Emission Spectroscopy
(EIES), a technology pioneered by INFICON, the system offers precise
control over MBE, UHV and HV processes as well as flexibility to meet
specialized needs in both production and development environments.
The light intensity of any material Ð the number of photons it emits Ð is
directly proportional to its number density in the sensor. The important
conclusion here is that light intensity can be used to measure evaporation
rate. And that's precisely what the Sentinel¨ III does.
Rate Control of Thin Film
Superconductive Materials
For high-vacuum processes that require the simultaneous evaporation of
materials such as Y, Ba and Cu in 1:2:3 atomic ratios, the Sentinel¨ III can
control individual deposition rates with proven reliability. By monitoring
each evaporant's optical emission line, the Sentinel¨ III combines material
selectivity with a sensitivity for the elements most frequently used in making
superconductive thin films.
Real-Time Feedback
During the process cycle, critical information is displayed in real time,
including thickness, source power, evaporation rate and rate deviation.
Sentinel¨ III measures evaporation rates and corrects source power
hundreds of times per minute.
Flexible System Integration
Internal and external I/0 displays provide programming flexibility for
complete system integration. The RS232 communications interface, in both
SECS II and lnficon formats, is standard; IEEE488 is available as an option.
EIES Sensor
Precision
The Sentinel¨ III is a remarkably precise instrument. Its sensor, with a life
exceeding 1,000 hours, offers rate sensitivity from 0.1 to 10,000 /sec.
Innovative Approach to
Challenging Applications
The Sentinel¨ can monitor and control the vapor flux, phasing and ratio
for two materials in alloy deposition. It can also control the evaporation
of Group IV materials in MBE applications. Even when deposition rates
are low over an extended period of time, as in MBE, when rates are
high with large material accumulations, as in terminal and backside
metallizations or web coating on thin, flexible substrates, the Sentinel ¨ III
meets the challenge.
Control System Components
B4.18