JPS60254043A - Developing agent for positive type photosensitive material - Google Patents

Abstract

PURPOSE:To facilitate formation of a prescribed shape positive image, to improve stability with lapse of time, and to reduce coloring due to lapse of time by using a specified quaterary ammonium hydroxide. CONSTITUTION:A positive type photosensitive resin is attached to a semiconductor, exposed to light through a mask, and the exposed layer is developed with a developing soln. contg. the quaternary ammonium hydroxide represented by the formula in which R<1>, R<2> are each 1-4C alkyl; and R<3>, R<4> are each 2, 3, or 4C alkylene, and when the carbon number of R<1>-R<4> exceeds 4, alkalinity drops and sufficient development effect cannot be attained. An ordinary concn. of the developing soln. is 0.5-20wt%, preferably, 1-15wt%. Said concn. needs to be >=0.5% from the point of development effect, and when >=20%, there is a danger of dissolving the unnexposed resist as well. Suitable development tims is changed in a wide range in accordance with the strength of the developer and the kinds of photosensitive materials actually used, and said time is usually in the range of one-several ten seconds.

Description

[Detailed description of the invention] The present invention relates to a developer for positive photosensitive materials.

[Purpose of the invention]

(Industrial Application Field) The present invention relates to the manufacture of semiconductor devices, etc., in which a positive photosensitive resin is applied to the semiconductor, exposed to light using a mask, and then a developer is applied to develop the exposed material. This is what we provide.

(Prior art) As such a developer, (however, !1, R2, R3, R4 are -CH3 1 -C
2H5 P-C3H7, -C4Hg, -C2H
401{ , -C3f{60H y-C4HgOH.

A positive type developer for materials sensitive to radiation such as electron beams, It is known (Japanese Unexamined Patent Publication No. 143019/1983).

As this developer, a large number of different compounds exist since each of R1 to R4 in the above general formula can be any of the above alkyl groups, hydroxyalkyl groups, and alkoxyalkyl groups.

Among these, for example, tetraalkylammonium hydroxide (D-a) contains Na. Alkali metals such as and C
Halogen atoms such as Z 2 and Br 2 are mixed in and become a factor that deteriorates the characteristics of the semiconductor.

Ti, +, +alkylmonohydroxyalkyl ammonium hydroxide (D-b) has poor stability over time, and after production it begins to become discolored, and after - days, the color tone changes to A.
It also becomes PRA300. Coloration is a phenomenon that occurs due to self-decomposition of D-b, which indicates that impurities are generated and purity is likely to decrease. Compounds whose purity tends to decrease as described above are not preferred as developers. A trialkylamine can be mentioned as a decomposition product of D-b. Trialkylamines, especially trimethylamine, have an amine odor and are not desirable in terms of the working environment. This amine odor is also due to the use of trialkylamine during synthesis.

Trimethylamine is designated as one of the malodorous substances under the Offensive Odor Prevention Act, and its release outside the system is prohibited, so it is necessary to suppress its generation as much as possible.

Furthermore, monoalkyl trihydroxylammonium hydroxide (D-c) and tetraalkoxyethylammonium hydroxy F (D-d) are D-a and u
Compared to -b, D-c and D-b have better stability over time and less oral coloring, but D-c and D-d have lower pH, so the concentration of the developer must be higher, and they are more susceptible to decomposition due to heat. Since the image quality is poor, there are problems with post-development processing. □ On the other hand, since D-a and 1)-bVipH are too high, the film becomes rough after development, making it difficult to obtain a fine pattern with high precision.

(Problems to be Solved by the Invention) The inventors of the present invention have conducted repeated research in order to obtain a developer free of the drawbacks as exemplified above, and as a result, have achieved the present invention.

[Structure of the invention]

(Means for solving the problems) That is, the present invention provides the following: (In the formula, R1 and R2 are alkyl groups having 1 to 4 carbon atoms, R3
, R4 represents an alkylene group having 2 to 4 carbon atoms. ) is a developer for positive photosensitive materials made of quaternary ammonium hydroxide.

(Function) After coating a semiconductor with a positive photosensitive resin and exposing it to light using a mask, the exposed layer is exposed to the fourth layer shown in the above-mentioned general public.
Developed with a developer consisting of grade ammonium hydroxide.

When the number of carbon atoms in R-R in the above general formula is greater than 4, alkalinity decreases and sufficient developing action is not exhibited.

Examples of compounds having the above general formula, that is, non-explosion developers are shown below. In the following formula, E+i represents an enalene group, P (represents a propylene group, and B represents a butylene group).

(Cf(3)(C2Hs)N(EOH),(Jl(1
(D-5), (c1■3)2N(POI()20H(J
J-6), (Cti, 3)2N(Fun)(POH
)OH(i)-7) and the like. These can be used singly or in combination with multiple silks.

The effecting agent of the present invention, ie, the above-mentioned quaternary ammonium hydroxide, can be produced, for example, by a method in which a secondary amine (R2NH) is reacted with an alkylene oxide in the presence of water.

The concentration of developer in solution can be used within a wide range, with the optimum concentration depending on characteristics such as the specific light-sensitive material to which the developer is applied and the desired development time. The concentration of developer in the solution is usually 0.5 to 20% by weight, preferably 1 to 15% by weight. Water or hydrophilic organic solvents such as methanol, ethanol, dioxane, etc. are used as solvents that require 0.5% or more in terms of development effect and may dissolve unexposed resist if the amount exceeds 20 cm. Can be used.

The photographic device adapted for use with the developer of the invention is imagewise exposed in a conventional manner by a source of actinic radiation.

As a pulley light source, a mercury lamp, a carbon arc lamp, a tungsten filament lamp, a fluorescent lamp, a laser beam, an electron beam, etc. are used.

The appropriate development time varies widely depending on the strength of the developer and the specific type of photosensitive material, and is usually in the range of 1 to several tens of seconds.

〔Example〕

Examples of manufacturing the developer of the present invention are shown below.

(Production example) 3,000 kg of a 21 wt% aqueous solution of dimethylamine was charged into a 5,000 t reactor, and the temperature was raised to 50 to 8 ml while stirring.
While maintaining the temperature at 0°C, ethylene oxide 1,233 was blown into ethylene oxide for 3 hours to react. 3 at the same temperature after blowing
After aging for 0 minutes, unreacted dimethylamine was recovered by topping and 4,200 Kr dimethyl (2-hydroxyethyl) ammonium hydroxide (D-1) was obtained.
A 50 wt aqueous solution was obtained.

Next, the invention will be explained and explained in more detail with reference to Examples and Comparative Examples.

(Examples and Comparative Examples) A positive photoresist was spin-coated onto a silicon wafer to produce a resist film having a resist film thickness of 1.5 μm. Next, the film was prebaked at 85° C. for 20 minutes, exposed to light using a mercury lamp, and developed by being immersed in an aqueous developer solution at 23° C. for 1 minute. Table 1 (Example) and Table 2 (Comparative Example) show the film thickness reduction rate (%) at each developer concentration.
Shown below.

Table 3 shows the results of differential thermal analysis regarding the thermal decomposition properties of each developer.

゛Also, Table 4 shows the results of comparing the temporal stability (APH, A) of each developer (io% aqueous solution) at room temperature.

Furthermore, Table 5 shows the pH of the 100% aqueous solution of each developer.

Table 1 (Example) Table 2 (Comparative Example) (Notes) D-I: Monomethyltri(2-hydroxyethyl)ammonium hydroxide D-B: Tetramethylammonium hydroxide D-Hanitrimethylmonohydroxyenal ammonium Hydroxide D-2: Monomethyltrimethoxyethylammonium hydroxide A3, 4, and 5 in the above table had a severe amine odor (decomposition odor) and required an exhaust device. However, roughness of the film was observed after development, and a highly accurate fine pattern could not be obtained.

Table-3 Table-4 $-5 Regarding developer, pH is an important factor, and 0.1 of pu
A slight difference of ~0.2 greatly affects the performance of the developer.

Developers with a pIl of less than a branch have poor performance, and those with a pIl of 12.7 or more cause film roughening, which is not preferred.

[Effects of the Invention] According to the developer of the present invention, a predetermined clear positive image tray can be easily obtained.

In addition, it has good stability over time and does not become discolored even after several days. Furthermore, there is no strong amine odor like in conventional developers. In addition,
Since no alkali metal or halogen atoms are mixed in, the properties of the semiconductor will not be degraded. Furthermore,
It has many practical advantages, such as its pH level meeting the requirements for a developing solution and its ability to be easily decomposed by heating after development.

Patent applicant Yokkaichi Gosei Co., Ltd.

Claims (1)

[Claims] (In the formula, al and a2 are alkyl groups having 1 to 4 carbon atoms,
R and R represent an alkylene group having 2 to 4 carbon atoms. ) 7 A developer for positive-working photosensitive materials consisting of quaternary ammonium hydroxide.