A method for controlling the burn-in temperature of a semiconductor chip includes determining a DC current of the chip, and determining a difference between the DC current and a target current, the target current being selected to produce a desired chip temperature. The method allows for the production of an LPS which can be used to produce a 3-O-deacylated monophosphoryl lipid A having at least about 20 mol % of the hexaacyl congener group. The metal members are configured to reduce zero-order transmitted light with respect to incident light, and to enhance diffraction efficiency of first-order transmitted light. The letters displayed on the keys have respective markings, such as a color, with each letter on a given key having a unique marking. Then a heat treatment is performed to activate the sourcedrain regions. The apparatus comprises an expansion device which may optionally comprise a membrane.