In the realm of high-end manufacturing, a chip the size of a fingernail, a lens as thin as a cicada's wing, or a precision sensor 

can all become scrap due to temperature fluctuations of just a fraction of a degree or minute humidity variations.

In the production of semiconductors, optical lenses, precision instruments, and other high-end products, the precision of 

temperature and humidity control directly determines the final yield rate. This article delves into how constant temperature 

and humidity machines have become indispensable safeguards in precision manufacturing and explores their application 

value across critical sectors.

01 The Butterfly Effect in the Microcosm: How Temperature and Humidity Fluctuations Impact Yield Rates

In precision manufacturing, temperature and humidity fluctuations act like a butterfly flapping its wings—minor changes 

trigger cascading reactions that ultimately cause significant drops in product yield rates.

Temperature variations induce thermal expansion and contraction in materials. If the thermal expansion coefficients of 

different materials are poorly matched, stress concentration occurs, leading to cracks or other structural damage.

During IC packaging, improper temperature control creates uneven stresses that can degrade IC performance or cause 

complete package failure.

Humidity acts as another invisible killer. Studies reveal over 25% of industrial defects stem from inadequate low-humidity storage.

In electronics manufacturing, moisture causes solder pad oxidation, leading to poor solderability. During IC packaging 

heating, it induces microcracking damage and may even trigger the “Manhattan effect” and “pillow effect” during reflow soldering.

For optical lenses, temperature and humidity fluctuations affect critical parameters like surface accuracy and refractive index. 

Exceeding tolerances can render the entire lens unusable.

02 Semiconductor Manufacturing: Nanometer-Level Precision in the Race Against Temperature

Semiconductor manufacturing demands extremely stringent temperature control precision, ranging from ±0.1°C to ±0.01°C.

As semiconductor processes advance, requirements for process environment and equipment temperature become increasingly 

demanding. In advanced packaging or automotive IC fields, temperature control precision must also reach ±0.1°C to ±0.01°C.

During wafer dicing, the temperature of the cutting water directly impacts yield rates. A study analyzed failure data from different 

cutting process water temperatures, identified root causes of anomalies, and determined the optimal cutting water temperature, 

significantly improving first-pass wafer dicing yield.

Thermal expansion matching is a critical consideration in IC packaging. Aligning the thermal expansion coefficients between 

semiconductor ICs and packaging materials is essential for long-term reliability.

Temperature variations cause thermal expansion and contraction in materials. Poor expansion matching between the IC and 

packaging materials can lead to stress concentration, potentially causing cracks or other structural damage.

Semiconductor components are highly vulnerable to packaging voids. Moisture ingress in humid environments can cause 

pin corrosion and circuit short-circuits. The Dual 85 Test (85°C high temperature + 85% RH high humidity) enables early 

detection of these risks, ensuring product reliability.

03 Precision Instruments and Laboratories: Pursuing Accuracy Through Stability

Precision instruments and laboratory environments also demand stringent temperature and humidity control. Within 

barrier system animal laboratories, environmental parameters undergo dynamic fluctuations that can influence experimental 

animals and consequently affect test outcomes.

Animals raised in barrier environments are particularly sensitive, necessitating strict control over the accuracy, precision, 

sensitivity, and representativeness of environmental parameters.

For camera modules, reliability testing encompasses environmental adaptation, mechanical/structural integrity, electrical/

electromagnetic compatibility, and more.

Environmental adaptation testing subjects cameras to rigorous conditions including high-temperature storage/operation, 

low-temperature storage/operation, constant humidity/heat cycles, and thermal shock.

Nucleic acid testing laboratories must also establish comprehensive environmental monitoring systems, conducting regular 

assessments through methods like air sedimentation and surface swabs to ensure accurate and reliable test results.

A constant temperature and humidity environment guarantees the accuracy and reliability of these precision tests and experiments.

04 The Technical Core of Constant Temperature and Humidity Units: The Science and Art of Precise Control

Achieving the constant temperature and humidity required for precision manufacturing relies on high-precision constant 

temperature and humidity machines. These devices provide stable environmental conditions, helping maintain manufacturing 

process consistency and thereby improving yield rates.

Take a high-precision constant temperature and humidity test chamber as an example. Its calibration process is extremely 

rigorous. Calibration must be conducted in an environment of (23±2)°C temperature and (50±5)% RH relative humidity to 

minimize external factors' impact on test results.

During temperature calibration, platinum resistance thermometers are evenly distributed within the chamber's working space. 

Multiple representative temperature points are established, and after each point stabilizes for 2 hours, the temperature data 

displayed by the high-precision temperature and humidity recorder and the chamber itself are recorded.

If the error exceeds the permissible range (e.g., ±0.5°C), the chamber's temperature control system must be adjusted and 

calibrated using temperature and humidity standards.

Modern high-precision temperature controllers display readings to two decimal places with a sampling time of just 25 

milliseconds and accuracy as high as ±0.1%, meeting the demands of high-precision manufacturing processes.

Some advanced constant temperature and humidity chambers also feature mode operation functionality. Each segment 

can be configured with PID group numbers, G.SOAK settings, and segment events, and is equipped with power failure 

recovery capabilities to ensure production continuity.

05 Quality Control and Testing: Simulating Extreme Environmental Challenges

In precision manufacturing, constant temperature and humidity chambers are not only used for environmental control 

during production but also widely applied in product quality testing.

The “Double 85” constant temperature and humidity test chamber (simulating 85°C high temperature + 85% RH high humidity) 

is a critical device for evaluating product reliability in the electronics industry.

This extreme environment accelerates the exposure of hidden defects in electronic components, acting as a “failure magnifier.”

Semiconductor components are most vulnerable to encapsulation leaks. Moisture ingress in humid-heat environments causes 

pin corrosion and circuit short-circuits. The Dual 85 test detects these hazards early.

Passive components also undergo rigorous testing: aluminum electrolytic capacitors leak and swell in humid-heat; multilayer 

ceramic capacitors may experience silver ion migration leading to breakdown; connector pins increase contact resistance due to oxidation.

Thermal shock testing is another demanding procedure, typically cycling between -40°C and +85°C within one minute, repeated 

50-100 times to evaluate the thermal stress tolerance of solder joints, adhesive layers, and structural components.

Alternating humidity and heat testing simulates condensation from day-night temperature variations. Conditions are typically 

25°C → 55°C → 25°C at 95% RH, cycled 10-20 times, to evaluate sealing integrity and material expansion/contraction properties.

From smartphone chips to high-end camera lenses, from medical devices to laboratory precision instruments, constant temperature 

and humidity chambers serve as the “soulmate” of precision manufacturing, silently safeguarding the birth of every high-end product.

Like an unwavering guardian, they provide stable temperature and humidity conditions for sensitive production environments, 

enabling technological innovation to thrive in optimal conditions.

In today's era of rapid technological advancement, reliable precision manufacturing is more critical than precision manufacturing 

itself. Constant temperature and humidity chambers form an indispensable component of the quality assurance system for high-end products.