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Process Development and Integration Laboratory Photovoltaic Research Process Development and Integration Laboratory

Process Development and Integration Design Features

The cluster tool and transport pod are at the heart of the research approach used within the Process Development and Integration Laboratory. In developing this approach, scientists in the National Center for Photovoltaics worked closely with their industry counterparts to design a system with maximum functionality and flexibility.

In this section, we refer to the schematic below to illustrate a process development and integration cluster tool and a transport pod. We also highlight some other critical design features. View a short animated video that explains seven terms related to sample measurements in the PDIL.

Schematic drawing is an overhead view showing a cluster tool where an articulated robotic arm is delivering a sample from one chamber around the central tool to another chamber. This type of transfer is an intra-tool transfer. On the right side of the drawing is a separate transfer pod that contains a sample. This pod has been detached from a second cluster tool and is being moved to the first cluster tool, where the sample can be removed by the robotic arm. This type of transfer is an inter-tool transfer.

Top-view schematic of cluster tools with intra-tool robotic sample transfer (left), and an illustration of an inter-tool sample transfer using transport pod (right) between cluster tools.


Illustration is a frame from the video animation. It shows an articulated robotic arm picking up a square sample from a transfer pod and getting ready to bring it inside the circular central transfer chamber, where it can be moved into one of the surrounding deposition or processing chambers.

The central robotic arm is delivering a sample (yellow square) to one of the depositional chambers connected to the tool.

Cluster Tool—A research cluster tool consists of modular depositional, processing, and characterization capabilities configured around a system in which samples are transferred using a central articulated robotic arm. This arm provides the mechanism for moving samples within a cluster tool. In these "intra-tool transfers," samples remain within a vacuum environment.


Illustration is a frame from the video animation. It shows a transfer pod, which is a separate unit on wheels that can hold samples within a vacuum chamber. The pod is being wheeled up to a special port on a cluster tool. Once the pod is connected to the port, the robotic arm within the cluster tool can pick up the sample and deliver it to other deposition and processing units surrounding the central transfer chamber.

The transfer pod (gray unit) contains samples being delivered from a remote tool to the tool on the right.

Mobile transport pod—A mobile transport pod is a special chamber used to transfer samples from one tool to another while maintaining the vacuum ambient condition. This type of sample transfer is called an "inter-tool" transfer. Using the transport pod prevents contamination or reactions on sample surfaces when moving samples between cluster tools. The pod thus eliminates the need for expensive cleanrooms and provides controlled-ambient access to expensive capabilities without the need to replicate these capabilities on cluster tools.


Illustration is a frame from the video animation. It shows a thin 6 inch by 6 inch sample sheet within a surrounding square frame below, with a slightly larger plate above that is ready to be attached to the frame to form a unit called a platen. A sample loaded within the platen can then be handled robotically.

The 157-mm by 157-mm sample shown in pink is held within the orange frame (below) and yellow back plate (above), which make up the platen.

Standard sample size and shape—The maximum sample size is 157 mm x 157 mm (just over 6 in. x 6 in.). A special metal frame—or platen—can hold samples of various sizes and shapes. The standard platen can be picked up and moved easily by an automated transfer system.


Illustration is a frame from the video animation. It shows a transfer pod, which is a separate unit on wheels that can hold samples within a vacuum chamber. The pod is being wheeled up to a port on a cluster tool. The pod has a special flange at a specific height that aligns with the port and provides a seal that maintains the vacuum condition between the pod and the central transfer chamber of the cluster tool.

The special flange (shown in orange) on the transport pod (left) allows the pod to be connected with a chamber (shown in purple) while maintaining a high vacuum.

Standard mechanical interface—The interface between the mobile transport pod and research cluster tool uses a centered 10-in. "conflat" flange, which is 1.1 m above the floor. This interface allows a tool to be aligned accurately before being connected to a port around the central transfer chamber, while also maintaining a vacuum seal.


Contact Martha Symko-Davies for more information on how we have made process development and integration possible.