Evaluation of surface temperature uniformity of multi-zone ceramic heaters with embedded cooling channels for electrostatic chuck

Development of a Hydrostatic Bearing in High Vacuum Using an Ionic Liquid for a Semiconductor Fabrication Device

“…Figure 6 (b) shows the time taken to reach 10 -5 Pa range and vacuum pressure at 2.5 h for the 3 conditions. The vacuum pressure reached at 2.5 h is almost the same for all three conditions, although the time is extended for condition (3).…”

“…The blue line in Fig. 6(a) represents condition (3), where the bearing mechanism and IL with the volume of 100 mL are introduced in the chamber; the time to reach a vacuum pressure of 10 -5 Pa is 2.09 h. As shown in this graph, the time to reach 10 -5 Pa is more, compared with conditions (1) and ( 2). However, in this experiment, vacuum pressures at 2.5 h with the 3 conditions is nearly the same, as shown in Fig.…”

“…However, the higher the vacuum level, the more difficult it is to control and remove heat. Currently, wafer heating is controlled by supplying helium gas [1,3] to a small gap between the backside of the wafer and the chuck in a low vacuum environment of 10 -3 Pa. To supply gas, multiple wafer chucking mechanisms (electrostatic chucks) make use of shallow gas channel grooves on their surface. In this cooling method, the wafer and chuck are in mechanical contact, resulting in non-uniform heat distribution on the wafer surface.…”

Analysis of surface temperature uniformity of temperature controlled wafer chuck based on fluid simulation

“…Wright, D. R et al [7] studied the heat transfer coefficient of inert gas in wafer chuck .Reference [8] studied the contact thermal resistance between the electrostatic chuck and the wafer; Literature [9] discusses the influence of thin gas on the heat transfer between the electrostatic chuck and the wafer, and establishes the analytical expression of gas heat transfer, which provides help for engineering design. Literature [10] studied the influence of coolant flow rate on temperature .Although some scholars have studied the temperature of the chuck, there is little concern about the uniformity of temperature. If the temperature of the wafer surface cannot be guaranteed to be as average as possible, the processing accuracy of the wafer will be greatly affected.…”