Thermoelectric micromodules

Thermoelectric microcoolers are usually singled out as a separate class not only by their dimensions (normally ≤10×10 mm) and the used dices dimensions (≤0.85×0.85 mm), but also in relation to special requirements for their applications.

Peltier microcoolers are applied for thermal stabilization of miniature objects such as solid-state lasers featuring high-density heat flows (up to 20 W /cm2). Besides, some applications of these modules, for example, telecommunications, specify high reliability requirements. The standard most frequently applied to determining reliability of Peltier micromodules is the Telcordia reliability control program.

Ferrotec Nord has a complete set of equipment to implement this reliability control program for high-volume output of micromodules.

Quality control of modules manufactured by Ferrotec Nord meets the Quality Assurance — internal quality standard which regulates all the intermediate and final inspection and testing operations.

Given below are some design and technological features representing the idea of Ferrotec Nord’s thermoelectric module production capabilities: 

  • Ceramic substrates — Al2O3 or AlN
  • Nonmetallized external surface; external surface metallization with Cu-Ni-Au on one side (Т version) or on two sides (ТТ version)
  • Various types of solders on the external metallization of modules (pretinning):
Solder type Melting point temperature, °C
Sn-In 112
Sn-In 139
In-Ag 143
Sn-In-Ag 175
Sn-Pb 183
Sn-Sb 230
  • Peltier module assembly solder — Sn-Sb (Тmelt ≈230оC), Au-Sn (Тmelt ≈280оC)
  • Thermoelectric modules are soldered with rosin fluxes or in influxless environment
  • At the customer’s request, terminals may be made from tinned or insulated wire or in the form of posts
  • Soldering quality is assured by gold plating of all soldering surfaces, both of the ceramic substrates and semiconductor dices
  • The washing line provides for 6-stage ultrasonic washing in different solvents and detergents that ensure perfect cleanliness of modules
  • Peltier cooler may be installed in standard package

Ferrotec Nord manufactures a wide range of Peltier micromodules, including those for use in TOSA (Transmitter Оptical Sub-Assembly).