Semiconductor substrate including a cooling channel and method of forming a semiconductor substrate including a cooling channel

A semiconductor substrate (12) for use in an integrated circuit includes a channel (22) defined on a surface (18) of the substrate (12). The channel (22) includes a first wall (24), a second wall (26), and a third wall (28). The first wall (24) is recessed from the surface (18). The second wall (26) extends from the surface (18) to the first wall (24). The third wall (28) extends from the surface (18) to the first wall (24) and faces the second wall (26) across the channel (22). At least one of the second wall (26) and the third wall (28) includes a plurality of structures (30) projecting into the channel (22) from the second wall (26) or the third wall (28).