Methods of forming semiconductor structures include providing a polymeric material over a carrier substrate, bonding another substrate to the polymeric material, and lowering a temperature of the polymeric material to below about 15° C. to separate the another substrate from the carrier substrate. Some methods include forming a polymeric material over a first substrate, securing a second substrate to the first substrate over the polymeric material, cooling the polymeric material to a temperature below a glass transition temperature of the polymeric material, and separating the second substrate from the first substrate. Semiconductor structures may include a polymeric material over at least a portion of a first substrate, an adhesive material over the polymeric material, and a second substrate over the adhesive material. The polymeric material may have a glass transition temperature of about 10° C. or lower and a melting point of about 100° C. or greater.