Spatially programmable temperature control and measurement for chemically amplified photoresist processing

Abstract

Preliminary performance data is presented for a new thermal processing module. ' :e system is directed towards conducting the temperature sensitive baking and chilling steps for chemically amplified photoresists. The module is comprised of 49 individual heating zones. The zones can be controlled independently with separate temperature sensing, actuation and feedback control mechanisms. A supervisory control strategy is applied to coordinate the individual zones. An in-situ chill plate is used to enable a temperature controlled cool-down phase without the need for substrate movement. Results are presented to demonstrate temperature control over the plate to within Wafer temperature is controlled to within as measured at 5 sites. Photomask processing results are presented depicting steady-state control to within as measured at 16 sites within one quadrant of the substrate. The advantages of the system are discussed including better temperature uniformity than conventional systems and the ability to conduct multiple experiments in a single run by biasing the setpomt across the substrate.

A lamp thermoelectricity based integrated bake/chill system for photoresist processing

“…The etched foil heater units also deflect during cyclings and thus raising the concern regarding long-term reliability. A considerable improvement was achieved in a spatially programmable module using an array of cartridge heaters developed by Kailath's group in Stanford [16,17] and subsequently commercialized. This system is excellent for processing substrates but without modification, it may not be able to achieve fast enough ramp-down rates during a thermal cycling operation.…”

“…Efforts in addressing some of these issues have been ongoing by our collaborators and us [14][15][16][17][18]. A fluid-heatexchanger based thermal cycling module was developed earlier [14,15].…”

Honey bee social foraging algorithms for resource allocation: Theory and application

“…Particularly relevant to our work is the study in EmamiNaeini et al (2003), where the authors use multivariable distributed control in order to maintain a uniform temperature across a wafer during ramp-up (similar to the control objective we study here). In Schaper et al (1999a) the authors describe a lithographical system that is heated by 49 independently controlled zones. Here, we use a multizone experimental setup that is similar to the one in Quijano et al (2005) where dynamic resource allocation methods are studied.…”

The Ideal Free Distribution: Theory and Engineering Application

“…Control goals like these arise in the context of a variety of commercial applications (e.g., building temperature control) industrial systems. For instance, in semiconductor processing, one challenge is to achieve a uniform temperature on a plate [16]. Others [17] study distributed control of wafer temperature via multizone rapid thermal processing systems.…”