If your laser package already contains a TEC module, you do not necessarily need a laser mount with another active TEC module. The integrated TEC in your laser diode package is typically sufficient in providing thermal stability to the laser diode, and an additional TEC module in the laser mount would not significantly increase thermal performance. Instead, you should select a mount that offers mechanical compatibility, plenty of thermal contact, and effective heat dissipation – this can be passive (finned heatsink) or active (integrated fan or water-cooling compatibility).
There are some scenarios in which a laser mount with an active TEC module can be used with a laser diode that has an integrated TEC. For example, some applications will require the device to be held at one temperature, while the laser mount is held at a different temperature. Additionally, a system with very high thermal loads may need additional active cooling to support the diode’s internal TEC module. It is important to consider that the user will need a temperature controller with multiple independent channels, or multiple temperature controllers to independently control each TEC module in an application. If your system requires the diode’s internal TEC, along with a TEC-cooled laser mount, you will need two temperature controllers/independent channels for this system.