Stresses in the system consisting of a heterojunction injection laser and a heat sink

A study is made of the mechanical properties of the bond between an injection laser and a heat sink over the temperature interval 289-423 K. An estimate is made of the stress that arises in the interior of the semiconductor crystal after it is soldered with indium to the copper base. The properties of the mechanical bond produced by the indium solder are analyzed at various uniform-heating temperatures. The analysis is based on measurements of the thermal strain of the system consisting of the injection laser and the heat sink. It is found that at room temperature, the stress arising in the interior of the semiconductor diode as a result of the soldering to the copper base can attain in a value comparable to the residual and thermoelastic stresses. With increasing temperature, the rigidity of the mechanical bond in the crystal-heat-sink system weakens significantly, so that the stress decreases.