The invention discloses a reaction chamber and a semiconductor device. A side wall of the chamber is covered with an annular lining, the lower side of the chamber is provided with a lower electrode, the lower electrode includes a chuck and a lifting part connected with the chuck, the chuck is used for bearing a chip, the lifting part is used for driving the chuck to rise and fall, and during a process, the lifting part drives the chuck to rise to a high position, so that the chip is surrounded by the lining; the chamber also includes a shielding part, during the process, the shielding part divides the chamber into an upper chamber and a lower chamber which are isolated, the chuck is located in the upper chamber, and the lifting part is located in the lower chamber; and after the process is finished, the lifting part drives the chuck to fall to a low position, and the upper chamber and the lower chamber are connected. During the process in the reaction chamber, the chip is surrounded by the lining, and chamber environment around the chip is symmetric, thereby improving consistency of chip surface process conditions, such as uniform distribution of plasma, and improving uniformity of an etching result.