Public Higher Education Bulletin

Purchase from Kurt J. Lesker Company Ltd their ALD-150LE. Only the ALD-150LE has: (i) multi-precursor liquid/solid/gas reactant input manifold with up to 7 reactants; (ii) pulsed gas reactant input; (iii) reactant delivery lines heated to 200 C; (iv) operating pressure up to 10 Torr; (v) substrate area of 150 mm in diameter; (vi) multiple real-time screens for all essential functions and variables of atomic layer deposition; (vii) excellent temperature uniformity across the entire substrate surface area; (viii) perpendicular flow reactor chamber for efficient gas/vapor delivery.

The ALD-150LE has a warm, not hot wall reactor which allows for independent control of substrate and chamber heating. Each has its own independent heater and control zone. The benefits of this are more process control, higher throughput because the entire chamber doesn?t need to be heated (it is much easier to heat the smaller substrate), and also the ability to quickly raise and lower substrate temperature.

Another significant advantage of a warm versus hot wall reactor is that the effects of gas phase reactions during ALD are a significant problem with Hot Wall designs because some degree of overlap between precursors during ALD processing is typically present (especially when shorter cycle times are being used) resulting in parasitic ALD effects. In this case, elevated reactor temperatures promotes gas phase reactions that generate particles detrimental to ALD film quality. In contrast, warm wall reactors (Kurt Lesker Design) have the added benefit of minimizing the potential for these gas phase reactions by reducing the chamber wall temperature relative to the substrate. Also, warm wall reactor designs are also inherently less energy intensive than hot wall designs since the high temperature heating is directed only to the substrate through the substrate heater.

The University has determined that this purchase is only economically available from this source because the items are required for research and no other source is able to meet the researcher's documented needs.