Vacuum tempering furnace system

---

Due to the rapid development of semiconductor industry, the research on vacuum tempering furnace system started early. The world’s first practical rapid annealing furnace system was launched by Varian, the largest semiconductor manufacturer in the United States. At present, the main production and research units of fast annealing furnace abroad are MPT, applied materials, Ag, Mattson and other companies in the United States; AST in Germany, jipelec in France, etc. These companies generally use lighting radiation heating.

There are two main technologies: one is the single point temperature measurement technology represented by Ag, MPT, AST and other companies in the United States, the other is the double-sided heating form with linear light source (lamp tube) as the heat source, and the silicon wafer is directly heated by the principle of infrared thermal radiation heating. The other is the unique multi-point side heating technology of American applied materials company. The heat source adopts the point light source (bulb) and single-sided heating form. The light from the spherical bulb enters the reaction chamber through the high transmittance quartz window to heat the silicon wafer on the silicon wafer support ring. The temperature signal detection side is detected in real time through a number of infrared probes with very fast response time, and the product is heating In the process of high-speed rotation, the contact probability between the wafer surface and the reaction gas is almost the same.

The stable rotating bracket drives the gas molecules on the wafer surface to form turbulent flow mode, which plays a great role in improving the uniformity of annealing degree, although the latter working form has a very good effect in temperature measurement and control accuracy and annealing uniformity But the structure design and control system design is very complex, so its price is also very expensive. Many semiconductor manufacturers are afraid. At present, only high-end IC manufacturing lines such as SMIC international are in use in China, and the rest of IC manufacturers generally use the former type of rapid annealing furnace system.

The vacuum tempering furnace is mainly composed of sub furnace shell, lining, heating element, furnace tank, vacuum system and electric control system.

Furnace shell: square structure welded by section steel and steel plate. Inside the furnace shell is a furnace which is made up of energy-saving refractory brick, refractory fiber felt and insulating brick. The heating element is made of 0cr25al5 high resistance alloy wire which is wound into a spiral coil. The spiral coil heating resistance wire is arranged on the wire laying brick on the two furnace walls of the furnace. There is a thermocouple temperature sensor on the top of the furnace.

Furnace tank: it is welded with 304 stainless steel, the bottom and cover of the furnace tank are hemispherical heads, and the front of the furnace tank is a double-layer water-cooled sandwich structure. The furnace cover and the furnace tank are sealed by an “O” type rubber ring and equipped with a locking device. The furnace tank is equipped with a heat shield device.

Vacuum system: it is composed of vacuum pump and corresponding valves. The vacuum valve is an electric control switch by button. The vacuum unit is equipped with charging and discharging valves, which can realize vacuum heat treatment or protective atmosphere heat treatment.

Electric control system: the imported digital temperature controller is adopted, with self-tuning PID function (with 8-stage process temperature program instrument, which can realize automatic heating or insulation according to the set process program). The main circuit adopts the current popular SSR solid-state relay, which has the characteristics of low noise, high temperature control precision and convenient operation. In addition, it also has the safety measures of water cut-off alarm automatic cut-off of the main circuit, over temperature alarm automatic cut-off of the main circuit. The electric control cabinet is backpack mounted on the right side of the furnace.

More：Vacuum tempering furnace system