Organic material deposition FAQ

A) the effective use of materials, low
Effective options currently available to manufacturers is very limited, the system designed to be extremely efficient use of expensive organic material and the dopant; Character LCD Display present utilization is generally lower than 10% or less, full-color lower utilization of the production process.
B) dopant (Dopant) is difficult to accurately control the concentration of
With dopant of 0.5 to 1% low dispersion rates, the result of the system, and temperature control, and the physical and chemical properties of the substance itself, such that the concentration ratio is not easy to control, and the concentration of the dopant is an important factor in the device structure, which makes the production process requires precision and maneuverability more difficult.
C) deposition rate instability
Deposition material purity and temperature control system approach led to deposition rate instability.
D) the coating uniformity of the substrate is not
This is mainly because the evaporation source and the heating boat design lack of specificity of the organic material.
E) contamination of the vacuum chamber
Because the material utilization is poor, lcd graphic display so causing a great part of the material may stick to the walls and other parts and become dust sources that affect the manufacturing yield of the device. For deposition coating uniformity enough, the Japanese VieetechJapan company provides a solution to the problem (see below), it is through the narrow mouth wide bottom and large capacity PBN crucible, providing an R & D and production applications loaded on organic material of the device. In particular, it is designed for organic materials Thermoball particles, poor thermal conductivity of organic materials can solve problem of low utilization and materials; with two-stage heating and temperature measurement, PID temperature control system, can be done in a timely manner and to achieve accurate temperature feedback Temperature differences within ± 0.1 ℃, can stabilize the evaporation rate; other special dopant DopantInsert and PID temperature control system, so that 0.5 to 1% of the proportion of constant and stable dopant.