NOVELTY - The method involves coupling a leaving group (303) with frame which consists of arbitrary atomic arrangements. The leaving group is detached by providing energy. Optimal excitation energy is identified for disconnecting the leaving group. The quantity of leaving group disconnected is measured by irradiating independently in time the energy-beam from which energy amount differs to the joining film. The quantity of disconnected leaving group is measured by measurement unit (13) and optimal excitation energy is identified from the quantity of the leaving group measured for every energy amount.    USE - Method for identifying excitation energy of energy-beam irradiated to joining film to join base material with to-be-adhered object. Uses include but are not limited to transistor, diode, semiconductor element, quartz oscillator, reflective mirror, solar cell, ink jet type recording head, pressure sensor, optical recording medium, LCD element, and micromirror.    ADVANTAGE - The energy amount and the quantity of the leaving group can be made to correspond easily and is measured at a high precision so that the optimal excitation energy is identified easily. The dimensional accuracy of the joined object becomes high so that the time required for hardening of an adhesive agent becomes unnecessary and is joined in a short time. The necessary and sufficient adhesiveness can be made and the deterioration of the joining film is prevented. The base material with joining film is conveyed by conveying unit so that the contaminations by air, operator, moisture, foreign material are prevented.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) excitation-energy identification apparatus;    (2) joining method; and    (3) joining apparatus.    DESCRIPTION OF DRAWING(S) - The drawing shows a front view showing irradiation of energy-beam to a joining film.(Drawing includes non-English language text)    Base material with joining film (1)    Sample mounting unit (11)    Ray source (12)    Measurement unit (13)    Leaving group (303)