Particle Dynamics in a Front-Opening Unified Pod/Load Port Unit Minienvironment in the Presence of a 300 mm Wafer in Various Positions

Figures & data

FIG. 1The FOUP/LPU minienvironment system.

FIG. 2 The docking processes.

FIG. 3The boundary conditions.

FIG. 4Schematic diagram of the four wafer positions (four cases).

Table 1 Case setup

Case	Description
Case1	No wafer is moved into the minienvironment
Case 2	The top wafer is moved into the minienvironment
Case 3	The middle wafer is moved into the minienvironment
Case 4	The bottom wafer is moved into the minienvironment

FIG. 5Particle concentration measuring and generation points.

FIG. 6The monitoring point for numerical grid independence tests.

FIG. 7Grid independence test for velocity.

FIG. 8Grid independence test for velocity.

FIG. 9The predicted versus measured velocity vectors for case 1: (a) measured velocity vectors, (b) predicted velocity vectors, and (c) streamtrace placement.

FIG. 10The predicted versus measured velocity vectors for case 2: (a) measured velocity vectors, (b) predicted velocity vectors, and (c) streamtrace placement.

FIG. 11The predicted versus measured velocity vectors for case 3: (a) measured velocity vectors, (b) predicted velocity vectors, and (c) streamtrace placement.

FIG. 12The predicted versus measured velocity vectors for case 4: (a) measured velocity vectors, (b) predicted velocity vectors, and (c) streamtrace placement.

Table 2 Predicted deposition ratio versus measured concentration ratio

		Deposition		Concentration
		ratio		ratio
Cases	Particle released point	FOUP	Wafer	M1	M2
Case 1	S1	0.752	—	0.484	—
	S2	0.493	—	0.103	—
	S3	0	—	0	—
Case 2	S1	0.273	0.006	0.283	0.061
	S2	0.202	0.001	0.218	0.053
	S3	0	0	0	0
Case 3	S1	0.633	0.001	0.708	0.048
	S2	0.043	0	0.032	0.013
	S3	0	0	0	0
Case 4	S1	0.792	0	0.927	0
	S2	0.271	0.013	0.697	0.018
	S3	0	0.005	0	0.006

FIG. 13(a) Velocity vectors (m/s), (b) pressure contours (Pa), (c) concentration contours (particles/m³) for a slight positive pressure differential case (dP = 0.18 Pa).

FIG. 14Pressure differential versus concentration ratio.