As a liquid metal with low flow stress, the liquid metal thermal interface materials are required to be specially packaged into an application to prevent leakage. Since gallium-containing liquid metals are corrosive to some materials and stick to others, the packaging materials must be carefully chosen.
A set of materials that I have worked with which were compatible with all the liquid metals are the Dupont Krytox products. There are a number of forms that these materials can be produced in, but the chemistry in any of these products makes them a good material fo r a dam surrounding the liquid metal.
These materials can be engineered for applications in both TIM1 and TIM2 applications.