The organic light emitting diode (OLED) is proposed as a novel source in the microchip because it has ideal merits (various wavelengths, thin-film structure and overall emitting) for the integration. In this paper, we fabricated finger-type PIN photodiodes for the fluorescence detection and an advanced microchip with an integrated OLED. The finger-type in the diode design extended the depletion region and its internal resistance was reduced about 32% than that of a rectangular-type. The photodiodes had 0.1 nA leakage current and 8,720 sensitivity (ILight/IDark) at -1 V bias. The interference filter with 32 layers (SiO2, TiO2) was directly deposited on the photodiode. Deposited OLEDs increased the excitation efficiency and extremely simplified the integration process. The monolithically integrated microchip had a high sensitivity of 0.256 nA/μM and the LOD (Limit of Detection, S/N =2) of 0.01 μM.