The method of metal chemical vapor deposition(MOVCD) was used to grow the GaAs/Al_0.3Ga_0.7As quantum well infrared photodetectors(QWIPs). The two sample-devices had large surface area 300 μm×300 μm. But its pressure welding area of electrode in was 20 μm×20 μm while that of the one out was 80 μm×80 μm. Their spectroscopic characteristics were measured at 77K by use of Fourier Transform Spectrometer. The results show that the peak wavelength of 1# and 2# are 8.43 μm and 8.32 μm respectively. While the theoretical one is 8.5μm according to Schrodinger equation. Thus the error between the experimental value and theoretical one of 1# and 2# are 1% and 2.1% respectively. Simulations demonstrate that metal chemical vapor deposition can satisfy quantum well infrared photodetectors processing needs and the different pressure welding area and position of electrode may has no influence on peak wavelength but has some influence on peak photocurrent.