The object of the contract includes the design, planning, construction and commissioning of a modern crystal growing plant, which is specially tailored to the requirements of liquid phase epitaxy (LPE). The planned facility is intended to create the ability to coat single-crystal substrate wafers with a diameter of 4 inches. In order to set the desired magnetic and optical functional properties, a whole series of process parameters must be precisely set and monitored.
The exact specifications and requirements are stored in the bill of quantities.
The object of the contract includes the design, planning, construction and commissioning of a modern crystal growing plant, which is specially tailored to the requirements of liquid phase epitaxy (LPE). The planned facility is intended to create the ability to coat single-crystal substrate wafers with a diameter of 4 inches. In order to set the desired magnetic and optical functional properties, a whole series of process parameters must be precisely set and monitored.
In the LPE process, the substrate wafers are immersed in a supercooled melt solution of Fe2O3, Bi2O3, Ga2O3, B2O3 and PbO at temperatures of 600 to 1250 ° C. A monocrystalline functional layer can be deposited by epitaxial crystal growth. In terms of plant technology, the high vapour pressure of lead oxide must be observed and appropriate safety precautions must be in place to exclude exposure of the environment to lead-containing compounds.
Essential process parameters of the system are a defined adjustable vertical temperature gradient in the furnace, as well as the possibility of moving crucibles and sample holders in time-programmable translation and rotation movements. In addition, the possibility is to be created to improve the homogenization of the melt by coupling a defined mechanical vibration into the crucible. It must be possible to reduce the start-up of the growing temperature by lowering the temperature of the melt by approx. 100 K to a period of a few hours by flowing through the furnace pipe with compressed air. Plant technical precautions must be taken to suppress the increased evaporation of lead oxide during the cooling phase. The system must also offer the possibility of thermally pre- and post-treatment of the wafers to be coated by suitable processing. The system must be offered as a complete system with all the installations necessary for coating 4-inch wafers, including power electronics, cooling water circulation system, exhaust air system and control and regulation system with PC.
The requirements for the individual process parameters must be found in the specifications. Further conditions are deposited in the attachment "Award conditions"!