| Name | photosensitive polyimide photoresist (PSPI) |
| Synonyms | photosensitive polyimide photoresist (PSPI) |
| Physical and Chemical Properties | The chemical properties are soluble and can be formulated into a heat-resistant photoresist. The main chain contains both a rigid aromatic ring and a flexible ether bond, so it has high thermal stability and toughness. Polyimide has many advantages and is a variety of functional polymer materials such as excellent heat resistance and photosensitive. |
| Use | Applications auxiliary materials used in the microelectronics industry can be used as interlayer insulation materials in the purification layer and large-scale integrated circuits. |
Synthesis of polyimide :
The synthesis of polyimide can be divided into two steps: polycondensation and cyclization. Phenylenetetraacid dianhydride and diaminodiphenyl ether are first condensed, and then dehydrated and cyclized to become polyimide.
Preparation of polyamic acid :
first, the strong polar solvent dimethylformamide or N-methylpyrrolidone or dimethylsulfoxide is added to the reactor, then 4,4 '-diaminodiphenyl ether is added, after stirring at 25 ℃ until it is completely dissolved, at 10-50 ℃, pyrotetraacid dianhydride is gradually added to the reactor under stirring, and finally 1%-2% excess of the anhydride is added to obtain polyamic acid.
Preparation of polyimide :
There are two ways to convert polyamic acid into imide compounds, one is thermal conversion and the other is chemical conversion. The thermal conversion method is to first remove the solvent to make polyamic acid in the shape of powder or film, and under the protection of inert gas, it is heated to 300-450 ℃ for dehydration and cyclization; the chemical conversion is to use dehydrating agent acetic anhydride and catalyst, etc. Polyimide is prepared directly from polyamic acid solution.
Cyclobutylimine Resin :
The dimer is prepared by chemical reaction of maleic anhydride, and then the polyimide is prepared by reaction with N,N'-diaminodiphenyl ether, and the cyclobutyl imide resin is obtained after dehydration, which is a positive photosensitive PI. After ultraviolet light irradiation, the exposed part can be dissolved in DMAc to obtain a micron-level image.
Synthesis of photosensitive polyimide :
The reaction of pyromellitic anhydride with propylene alcohol produces diallyl pyromellitic acid.
Production of polyimide drawing lines.
preparation of photosensitive liquid :
methyl pyrrolidone is added with cyclohexanone leveling agent as a mixed solvent to prepare a mixed solvent according to a ratio of 1:1 (volume ratio), and the sensitizer mierone is dissolved in the mixed solvent according to a certain ratio to prepare a sensitizing system solution with a mass fraction of 5%-10%, and then dissolve the photosensitive resin in the mixed solvent according to the mass fraction of 30%, and then add a certain amount of sensi, stir evenly, then add appropriate additives, after stirring, standing and precision filter pressure filtration, is the photosensitive liquid.