JP4533660B2 - Positive photosensitive composition and pattern forming method using the same - Google Patents

Description

  The present invention relates to a positive photosensitive composition used in a semiconductor manufacturing process such as an IC, a circuit board such as a liquid crystal or a thermal head, and other photofabrication processes, and a pattern forming method using the same. is there. More specifically, the present invention relates to a positive photosensitive composition suitable for use as an exposure light source such as far ultraviolet rays of 220 nm or less and an irradiation source using an electron beam, and a pattern forming method using the same.

  The chemically amplified positive photosensitive composition generates an acid in the exposed area by irradiation with radiation such as far ultraviolet light, and reacts with the developer of the active radiation irradiated area and the non-irradiated area by a reaction using this acid as a catalyst. It is a pattern forming material for changing solubility and forming a pattern on a substrate.

  When a KrF excimer laser is used as an exposure light source, a resin having a basic skeleton of poly (hydroxystyrene) having a small absorption mainly in the 248 nm region is used as a main component. A pattern is formed, which is a better system than the conventional naphthoquinone diazide / novolak resin system.

On the other hand, when a further short wavelength light source, for example, an ArF excimer laser (193 nm) is used as an exposure light source, the compound having an aromatic group exhibits a large absorption in the 193 nm region. It wasn't.
For this reason, an ArF excimer laser resist containing a resin having an alicyclic hydrocarbon structure has been developed.
Furthermore, it has been found that the performance can be improved by adding a repeating unit having a lactone structure to the resin having the alicyclic hydrocarbon structure. Patent Document 1 (Japanese Patent Laid-Open No. 9-73173) and Patent Document 2 (US Pat. No. 6,388,101B) describe resist compositions using a resin containing a repeating unit having a mevalonic lactone structure or a γ lactone structure. In addition, Patent Document 3 (Japanese Patent Laid-Open No. 2000-159758), Patent Document 4 (Japanese Patent Laid-Open No. 2001-109154), and Patent Document 5 (US Patent Publication No. 2001-26901A) disclose alicyclic rings. A resist composition using a resin containing a repeating unit having a lactone structure is described.
However, from the viewpoint of overall performance as a resist, it is actually difficult to find an appropriate combination of resin, photoacid generator, additive, solvent, etc. to be used, and the line width is 100 nm or less. When forming such a fine pattern, improvement of the line edge roughness performance of the line pattern as well as the resolving power has been demanded.
Here, the line edge roughness means that the resist line pattern and the edge of the substrate interface exhibit irregular shapes in a direction perpendicular to the line direction due to the characteristics of the resist. When this pattern is observed from directly above, the edges appear to be uneven (± several nm to several tens of nm). Since the unevenness is transferred to the substrate by an etching process, if the unevenness is large, an electrical characteristic defect is caused and the yield is lowered.

JP-A-9-73173 US Pat. No. 6,388,101B JP 2000-159758 A JP 2001-109154 A US Patent No. 2001-26901A

  Accordingly, an object of the present invention is to provide a positive photosensitive composition which is excellent in resolving power and improved in line edge roughness even in the formation of a fine pattern of 100 nm or less, and a pattern forming method using the same. is there.

  The present invention is a positive photosensitive composition having the following constitution and a pattern forming method using the same, whereby the above object of the present invention is achieved.

一般式（Ｉ）に於いて、
Ｌ₁は、単環又は多環の（ｍ＋１）価の脂環炭化水素基を表す。
Ｘ₁は、単結合又は２価の連結基を表す。
Ｌｃ₁は、ラクトン構造を有する基を表す。
ｍは、１又は２の整数を表す。

ここで、Ｒは、水素原子、ハロゲン原子又は１〜４個の炭素原子を有する直鎖もしくは分岐のアルキル基を表す。複数のＲは、各々同じでも異なっていてもよい。
Ａは、単結合、アルキレン基、エーテル基、チオエーテル基、カルボニル基、エステル基、アミド基、スルフォンアミド基、ウレタン基、又はウレア基よりなる群から選択される単独あるいは２つ以上の基の組み合わせを表す。 Ｒａは、下記一般式（ｐＩ）〜（ｐＶＩ）のいずれかで表される基を表す。

式中、Ｒ₁₁は、メチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、イソブチル基又はｓｅｃ−ブチル基を表し、Ｚは、炭素原子とともに脂環式炭化水素基を形成するのに必要な原子団を表す。
Ｒ₁₂〜Ｒ₁₆は、各々独立に、炭素数１〜４個の、直鎖もしくは分岐のアルキル基又は脂環式炭化水素基を表し、但し、Ｒ₁₂〜Ｒ₁₄のうち少なくとも１つ、もしくはＲ₁₅、Ｒ₁₆のいずれかは脂環式炭化水素基を表す。
Ｒ₁₇〜Ｒ₂₁は、各々独立に、水素原子、炭素数１〜４個の、直鎖もしくは分岐のアルキル基又は脂環式炭化水素基を表し、但し、Ｒ₁₇〜Ｒ₂₁のうち少なくとも１つは脂環式炭化水素基を表す。また、Ｒ₁₉、Ｒ₂₁のいずれかは炭素数１〜４個の、直鎖もしくは分岐のアルキル基又は脂環式炭化水素基を表す。
Ｒ₂₂〜Ｒ₂₅は、各々独立に、水素原子、炭素数１〜４個の、直鎖もしくは分岐のアルキル基又は脂環式炭化水素基を表し、但し、Ｒ₂₂〜Ｒ₂₅のうち少なくとも１つは脂環式炭化
水素基を表す。また、Ｒ₂₃とＲ₂₄は、互いに結合して環を形成していてもよい。

式中、Ｒ¹は水素原子又はメチル基、Ｒ²、Ｒ³は水素原子、又は炭素数１〜１５の直鎖状、分岐状もしくは環状のアルキル基を表し、Ｒ²とＲ³は結合して環を形成してもよく、その場合には、Ｒ²とＲ³で炭素数２〜１５の直鎖状、分岐状又は環状のアルキレン基を表す。Ｘは−ＣＨ₂−、−ＣＨ₂ＣＨ₂−もしくは−Ｏ−又は互いに分離した２個の−Ｈであることを表す。点線はノルボルナン環、ビシクロ［２．２．２］オクタン環、７−オキサノルボルナン環、又はシクロヘキサン環構造とγ−ブチロラクトン環構造とを結合する単結合、二価の有機基又はこれら両環構造間で一個又は二個の構成炭素原子を共有する構造を表す。
（ア）（Ａ）下記一般式（Ｉ_０）で表される部分構造を有する繰り返し単位と、下記一般式（II）で表される繰り返し単位を含有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、（Ｂ）活性光線または放射線の照射により酸を発生する化合物、を含有するポジ型フォトレジスト組成物。

式（Ｉ_０）中、ｍ１は１から６の整数を表す。Ｒ¹及びＲ²はそれぞれアルキル基もしくは環状アルキル基を表し、又はＲ¹とＲ²が互いに結合して環状アルキル基を形成してもよい。Ｒ³及びＲ⁴はそれぞれ水素原子、アルキル基もしくは環状アルキル基を表し、又はＲ³とＲ⁴が互いに結合して環状アルキル基を形成してもよい。Ｒ⁵〜Ｒ⁷はそれぞれアルキル基、環状アルキル基、アリール基、アリル基、トリアルキルシリル基又はトリアルキルシリルオキシ基を表す。

式（II）中、Ｙは水素原子、メチル基、シアノ基、塩素原子から選ばれる基を表す。Ｌ¹は単結合または２価の連結基を表す。Ｘ¹は−ＣＯ₂−、−Ｏ−、−ＣＯＮＨ−、−ＣＯＮ(Ｒ)−から選ばれる基を表す。ここでＲは置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。Ａはラクトン構造を含む基、ラクタム構造を含む基、置換基として−ＯＨ、−ＯＣＨ₃、−ＯＣＯＲａ、−ＯＣＯＯＲａ、−ＯＣＯＮＨＲａ、−ＯＣＯＮ(Ｒａ)(Ｒｂ)、−ＮＨＣＯＲａ、−ＮＨＣＯＯＲａ、−ＮＨＳＯ₂Ｒａ、−Ｎ(Ｒ)ＣＯＲａ、−Ｎ(Ｒ)ＣＯＯＲａ、−Ｎ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＯＲ、−ＣＯＮＨＲａ、−ＣＯＮＨＳＯ₂Ｒａ、−ＣＯＮ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＮ(Ｒａ)(Ｒｂ)、−ＣＮの群から選ばれる少なくとも１つの官能基を含有する飽和脂肪族基を表す。ここでＲ、Ｒａ、Ｒｂはそれぞれ独立に置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。
（イ）（Ａ）下記一般式（Ｉａ）及び（Ｉｂ）のうち少なくともいずれかで表される繰り返し単位と、下記一般式（Ｉｃ）で表される繰り返し単位を含有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、（Ｂ）活性光線または放射線の照射により酸を発生する化合物を含有するポジ型フォトレジスト組成物。

式（Ｉａ）中、Ｙは水素原子、メチル基、シアノ基、塩素原子から選ばれる基を表す。Ｌは単結合または２価の連結基を表す。Ｒ¹〜Ｒ⁴はそれぞれ独立に水素原子、ＳｉＲ'(Ｒ'')(Ｒ''')、置換基としてＳｉＲ'(Ｒ'')(Ｒ''')を含んでも良いアルキル基を表す。但し、Ｒ¹〜Ｒ⁴の全てが水素原子になることはない。Ｒ'、Ｒ''、Ｒ'''はそれぞれ独立に直鎖または分岐を有するアルキル基、フェニル基、トリアルキルシリル基、トリアルキルシリルオキシ基を表す。

式（Ｉｂ）中、Ｘ¹は酸素原子、硫黄原子、炭素数１〜３のアルキレン基を表す。Ｌ、Ｒ¹〜Ｒ⁴、Ｒ'、Ｒ''、Ｒ'''は前記と同義である。

式（Ｉｃ）中、Ｙ、Ｌは前記式（Ｉａ）におけるのと同義である。Ｘ²は−ＣＯ₂−、−Ｏ−、−ＣＯＮＨ−、−ＣＯＮ(Ｒ)−から選ばれる基を表す。ここでＲは置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。Ａはラクトン構造を含む基、ラクタム構造を含む基、置換基として−ＯＣＨ₃、−ＯＣＯＲａ、−ＯＣＯＯＲａ、−ＯＣＯＮＨＲａ、−ＯＣＯＮ(Ｒａ)(Ｒｂ)、−ＮＨＣＯＲａ、−ＮＨＣＯＯＲａ、−ＮＨＳＯ₂Ｒａ、−Ｎ(Ｒ)ＣＯＲａ、−Ｎ(Ｒ)ＣＯＯＲａ、−Ｎ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＯＨ、−ＣＯＯＲ、−ＣＯＮＨＲａ、−ＣＯＮＨＳＯ₂Ｒａ、−ＣＯＮ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＮ(Ｒａ)(Ｒｂ)、−ＣＮの群から選ばれる少なくとも１つの官能基を含有する飽和脂肪族基を表す。ここでＲ、Ｒａ、Ｒｂはそれぞれ独立に置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。

一般式（ＡＩ）中、Ｒ_b0は、水素原子、ハロゲン原子、又は炭素数１〜４のアルキル基を表す。
Ａ’は、単結合、エーテル基、エステル基、カルボニル基、アルキレン基、又はこれらを組み合わせた２価の基を表す。
Ｂ₂は、一般式（Ｌｃ）又は一般式（Ｖ−１）〜（Ｖ−５）のうちのいずれかで示される基を表す。

一般式（Ｌｃ）中、Ｒａ₁，Ｒｂ₁，Ｒｃ₁，Ｒｄ₁，Ｒｅ₁は、各々独立に、水素原子又はアルキル基を表す。ｍ，ｎは各々独立に０〜３の整数を表し、ｍ＋ｎは、２以上６以下である。
一般式（Ｖ−１）〜（Ｖ−５）において、Ｒ_1b〜Ｒ_5bは、各々独立に、水素原子、アルキル基、シクロアルキル基、アルコキシ基、アルコキシカルボニル基、アルキルスルホニルイミノ基又はアルケニル基を表す。Ｒ_1b〜Ｒ_5bの内の２つは、結合して環を形成してもよい。
＜２＞
（Ａ）下記一般式（Ｉ）で表される基を有する繰り返し単位、下記一般式（ＡII）で示される繰り返し単位及び下記一般式（ＡＩ）で表される繰り返し単位を有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、及び、
（Ｂ）活性光線又は放射線の照射により酸を発生する化合物
を含有することを特徴とするポジ型感光性組成物（但し、下記（ア）及び（イ）を除く）。

一般式（Ｉ）に於いて、
Ｌ₁は、単環又は多環の（ｍ＋１）価の脂環炭化水素基を表す。
Ｘ₁は、単結合又は２価の連結基を表す。
Ｌｃ₁は、ラクトン構造を有する基を表す。
ｍは、１又は２の整数を表す。

一般式（ＡII）中、Ｒ₁cは、水素原子又はメチル基を表す。
Ｒ₂c〜Ｒ₄cは、各々独立に水素原子又は水酸基を表す。ただし、Ｒ₂c〜Ｒ₄cのうち少なくとも１つは水酸基を表す。
（ア）（Ａ）下記一般式（Ｉ_０）で表される部分構造を有する繰り返し単位と、下記一般式（II）で表される繰り返し単位を含有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、（Ｂ）活性光線または放射線の照射により酸を発生する化合物、を含有するポジ型フォトレジスト組成物。

式（Ｉ_０）中、ｍ1は１から６の整数を表す。Ｒ¹及びＲ²はそれぞれアルキル基もしくは環状アルキル基を表し、又はＲ¹とＲ²が互いに結合して環状アルキル基を形成してもよい。Ｒ³及びＲ⁴はそれぞれ水素原子、アルキル基もしくは環状アルキル基を表し、又はＲ³とＲ⁴が互いに結合して環状アルキル基を形成してもよい。Ｒ⁵〜Ｒ⁷はそれぞれアルキル基、環状アルキル基、アリール基、アリル基、トリアルキルシリル基又はトリアルキルシ
リルオキシ基を表す。

式（II）中、Ｙは水素原子、メチル基、シアノ基、塩素原子から選ばれる基を表す。Ｌ¹は単結合または２価の連結基を表す。Ｘ¹は−ＣＯ₂−、−Ｏ−、−ＣＯＮＨ−、−ＣＯＮ(Ｒ)−から選ばれる基を表す。ここでＲは置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。Ａはラクトン構造を含む基、ラクタム構造を含む基、置換基として−ＯＨ、−ＯＣＨ₃、−ＯＣＯＲａ、−ＯＣＯＯＲａ、−ＯＣＯＮＨＲａ、−ＯＣＯＮ(Ｒａ)(Ｒｂ)、−ＮＨＣＯＲａ、−ＮＨＣＯＯＲａ、−ＮＨＳＯ₂Ｒａ、−Ｎ(Ｒ)ＣＯＲａ、−Ｎ(Ｒ)ＣＯＯＲａ、−Ｎ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＯＲ、−ＣＯＮＨＲａ、−ＣＯＮＨＳＯ₂Ｒａ、−ＣＯＮ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＮ(Ｒａ)(Ｒｂ)、−ＣＮの群から選ばれる少なくとも１つの官能基を含有する飽和脂肪族基を表す。ここでＲ、Ｒａ、Ｒｂはそれぞれ独立に置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。
（イ）（Ａ）下記一般式（Ｉａ）及び（Ｉｂ）のうち少なくともいずれかで表される繰り返し単位と、下記一般式（Ｉｃ）で表される繰り返し単位を含有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、（Ｂ）活性光線または放射線の照射により酸を発生する化合物を含有するポジ型フォトレジスト組成物。

式（Ｉａ）中、Ｙは水素原子、メチル基、シアノ基、塩素原子から選ばれる基を表す。Ｌは単結合または２価の連結基を表す。Ｒ¹〜Ｒ⁴はそれぞれ独立に水素原子、ＳｉＲ'(Ｒ'')(Ｒ''')、置換基としてＳｉＲ'(Ｒ'')(Ｒ''')を含んでも良いアルキル基を表す。但し、Ｒ¹〜Ｒ⁴の全てが水素原子になることはない。Ｒ'、Ｒ''、Ｒ'''はそれぞれ独立に直鎖または分岐を有するアルキル基、フェニル基、トリアルキルシリル基、トリアルキルシリルオキシ基を表す。

式（Ｉｂ）中、Ｘ¹は酸素原子、硫黄原子、炭素数１〜３のアルキレン基を表す。Ｌ、Ｒ¹〜Ｒ⁴、Ｒ'、Ｒ''、Ｒ'''は前記と同義である。

式（Ｉｃ）中、Ｙ、Ｌは前記式（Ｉａ）におけるのと同義である。Ｘ²は−ＣＯ₂−、−Ｏ−、−ＣＯＮＨ−、−ＣＯＮ(Ｒ)−から選ばれる基を表す。ここでＲは置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。Ａはラクトン構造を含む基、ラクタム構造を含む基、置換基として−ＯＣＨ₃、−ＯＣＯＲａ、−ＯＣＯＯＲａ、−ＯＣＯＮＨＲａ、−ＯＣＯＮ(Ｒａ)(Ｒｂ)、−ＮＨＣＯＲａ、−ＮＨＣＯＯＲａ、−ＮＨＳＯ₂Ｒａ、−Ｎ(Ｒ)ＣＯＲａ、−Ｎ(Ｒ)ＣＯＯＲａ、−Ｎ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＯＨ、−ＣＯＯＲ、−ＣＯＮＨＲａ、−ＣＯＮＨＳＯ₂Ｒａ、−ＣＯＮ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＮ(Ｒａ)(Ｒｂ)、−ＣＮの群から選ばれる少なくとも１つの官能基を含有する飽和脂肪族基
を表す。ここでＲ、Ｒａ、Ｒｂはそれぞれ独立に置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。

一般式（ＡＩ）中、Ｒ_b0は、水素原子、ハロゲン原子、又は炭素数１〜４のアルキル基を表す。
Ａ’は、単結合、エーテル基、エステル基、カルボニル基、アルキレン基、又はこれらを組み合わせた２価の基を表す。
Ｂ₂は、一般式（Ｌｃ）又は一般式（Ｖ−１）〜（Ｖ−５）のうちのいずれかで示される基を表す。

一般式（Ｌｃ）中、Ｒａ₁，Ｒｂ₁，Ｒｃ₁，Ｒｄ₁，Ｒｅ₁は、各々独立に、水素原子又はアルキル基を表す。ｍ，ｎは各々独立に０〜３の整数を表し、ｍ＋ｎは、２以上６以下である。
一般式（Ｖ−１）〜（Ｖ−５）において、Ｒ_1b〜Ｒ_5bは、各々独立に、水素原子、アルキル基、シクロアルキル基、アルコキシ基、アルコキシカルボニル基、アルキルスルホニルイミノ基又はアルケニル基を表す。Ｒ_1b〜Ｒ_5bの内の２つは、結合して環を形成してもよい。
＜３＞
一般式（Ｉ）で表される基を有する繰り返し単位が、下記一般式（Ｉ'）で表されることを特徴とする上記＜１＞又は＜２＞に記載のポジ型感光性組成物。

一般式（Ｉ’）に於いて、
Ｒａ₁は、水素原子、アルキル基又は−ＣＨ₂−Ｏ−Ｒａ₂基を表す。式中、Ｒａ₂は、水素原子、アルキル基又はアシル基を表す。
Ｌ₁は、単環又は多環の（ｍ＋１）価の脂環炭化水素基を表す。
Ｘ₁は、単結合又は２価の連結基を表す。
Ｌｃ₁は、ラクトン構造を有する基を表す。
ｍは、１又は２の整数を表す。
＜４＞
一般式（Ｉ）又は 一般式（Ｉ’）に於いて、Ｌ₁が、シクロペンタン、シクロヘキサン、ノルボルナン、アダマンタン、トリシクロデカン及びテトラシクロドデカンから選ばれる単環又は多環の（ｍ＋１）価の脂環炭化水素基であることを特徴とする上記＜１＞〜＜３＞のいずれかに記載のポジ型感光性組成物。
＜５＞
（Ａ）下記一般式（１）〜（３）のいずれかで表される繰り返し単位及び下記一般式（ＡII）で示される繰り返し単位を有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、及び、
（Ｂ）活性光線又は放射線の照射により酸を発生する化合物
を含有することを特徴とするポジ型感光性組成物（但し、下記（ア）及び（イ）を除く）。

Ｒａ₁は、水素原子、アルキル基又は−ＣＨ₂−Ｏ−Ｒａ₂基を表す。式中、Ｒａ₂は、水素原子、アルキル基又はアシル基を表す。
Ｘ₁は、単結合又は２価の連結基を表す。
Ｌｃ₁は、ラクトン構造を有する基を表す。
Ｒｂ₁は、置換基を表し、複数個存在する場合は同一でも異なっていてもよい。
ｎ_１は、０〜３の整数を表す。

一般式（ＡII）中、Ｒ₁cは、水素原子又はメチル基を表す。
Ｒ₂c〜Ｒ₄cは、各々独立に水素原子又は水酸基を表す。ただし、Ｒ₂c〜Ｒ₄cのうち少なくとも１つは水酸基を表す。
（ア）（Ａ）下記一般式（Ｉ_０）で表される部分構造を有する繰り返し単位と、下記一般式（II）で表される繰り返し単位を含有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、（Ｂ）活性光線または放射線の照射により酸を発生する化合物、を含有するポジ型フォトレジスト組成物。

式（Ｉ_０）中、ｍ1は１から６の整数を表す。Ｒ¹及びＲ²はそれぞれアルキル基もしくは環状アルキル基を表し、又はＲ¹とＲ²が互いに結合して環状アルキル基を形成してもよい。Ｒ³及びＲ⁴はそれぞれ水素原子、アルキル基もしくは環状アルキル基を表し、又はＲ³とＲ⁴が互いに結合して環状アルキル基を形成してもよい。Ｒ⁵〜Ｒ⁷はそれぞれアルキル基、環状アルキル基、アリール基、アリル基、トリアルキルシリル基又はトリアルキルシリルオキシ基を表す。

式（II）中、Ｙは水素原子、メチル基、シアノ基、塩素原子から選ばれる基を表す。Ｌ¹は単結合または２価の連結基を表す。Ｘ¹は―ＣＯ₂―、−Ｏ−、―ＣＯＮＨ―、―ＣＯＮ(Ｒ)―から選ばれる基を表す。ここでＲは置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。Ａはラクトン構造を含む基、ラクタム構造を含む基、置換基として−ＯＨ、−ＯＣＨ₃、−ＯＣＯＲａ、−ＯＣＯＯＲａ、−ＯＣＯＮＨＲａ、−ＯＣＯＮ(Ｒａ)(Ｒｂ)、−ＮＨＣＯＲａ、−ＮＨＣＯＯＲａ、−ＮＨＳＯ₂Ｒａ、−Ｎ(Ｒ)ＣＯＲａ、−Ｎ(Ｒ)ＣＯＯＲａ、−Ｎ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＯＲ、−ＣＯＮＨＲａ、−ＣＯＮＨＳＯ₂Ｒａ、−ＣＯＮ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＮ(Ｒａ)(Ｒｂ)、−ＣＮの群から選ばれる少なくとも１つの官能基を含有する飽和脂肪族基を表す。ここでＲ、Ｒａ、Ｒｂはそれぞれ独立に置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。
（イ）（Ａ）下記一般式（Ｉａ）及び（Ｉｂ）のうち少なくともいずれかで表される繰り返し単位と、下記一般式（Ｉｃ）で表される繰り返し単位を含有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、（Ｂ）活性光線または放射線の照射により酸を発生する化合物を含有するポジ型フォトレジスト組成物。

式（Ｉａ）中、Ｙは水素原子、メチル基、シアノ基、塩素原子から選ばれる基を表す。Ｌは単結合または２価の連結基を表す。Ｒ¹〜Ｒ⁴はそれぞれ独立に水素原子、ＳｉＲ'(Ｒ'')(Ｒ''')、置換基としてＳｉＲ'(Ｒ'')(Ｒ''')を含んでも良いアルキル基を表す。但し、Ｒ¹〜Ｒ⁴の全てが水素原子になることはない。Ｒ'、Ｒ''、Ｒ'''はそれぞれ独立に直鎖または分岐を有するアルキル基、フェニル基、トリアルキルシリル基、トリアルキルシリルオキシ基を表す。

式（Ｉｂ）中、Ｘ¹は酸素原子、硫黄原子、炭素数１〜３のアルキレン基を表す。Ｌ、Ｒ¹〜Ｒ⁴、Ｒ'、Ｒ''、Ｒ'''は前記と同義である。

式（Ｉｃ）中、Ｙ、Ｌは前記式（Ｉａ）におけるのと同義である。Ｘ²は―ＣＯ₂―、−Ｏ−、―ＣＯＮＨ―、―ＣＯＮ(Ｒ)―から選ばれる基を表す。ここでＲは置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。Ａはラクトン構造を含む基、ラクタム構造を含む基、置換基として−ＯＣＨ₃、−ＯＣＯＲａ、−ＯＣＯＯＲａ、−ＯＣＯＮＨＲａ、−ＯＣＯＮ(Ｒａ)(Ｒｂ)、−ＮＨＣＯＲａ、−ＮＨＣＯＯＲａ、−ＮＨＳＯ₂Ｒａ、−Ｎ(Ｒ)ＣＯＲａ、−Ｎ(Ｒ)ＣＯＯＲａ、−Ｎ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＯＨ、−ＣＯＯＲ、−ＣＯＮＨＲａ、−ＣＯＮＨＳＯ₂Ｒａ、−ＣＯＮ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＮ(Ｒａ)(Ｒｂ)、−ＣＮの群から選ばれる少なくとも１つの官能基を含有する飽和脂肪族基を表す。ここでＲ、Ｒａ、Ｒｂはそれぞれ独立に置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。
＜６＞
（Ａ）下記一般式（４）で表される繰り返し単位及び下記一般式（ＡII）で示される繰り返し単位を有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、及び、 （Ｂ）活性光線又は放射線の照射により酸を発生する化合物
を含有することを特徴とするポジ型感光性組成物（但し、下記（ア）及び（イ）を除く）。

Ｒａ₁は、水素原子、アルキル基又は−ＣＨ₂−Ｏ−Ｒａ₂基を表す。式中、Ｒａ₂は、水素原子、アルキル基又はアシル基を表す。
Ｒｂ₁は、置換基を表し、複数個存在する場合は同一でも異なっていてもよい。
ｎ_１は、０〜３の整数を表す。
Ｘ₁は、単結合又は２価の連結基を表す。
Ｌｃ₁は、下記一般式（ＬＣ１−１）又は（ＬＣ１−２）で表されるラクトン構造を有する基を表す。

ｎ_２は、０〜３の整数を表す。
Ｒｂ₂は、置換基を表す。

一般式（ＡII）中、Ｒ₁cは、水素原子又はメチル基を表す。
Ｒ₂c〜Ｒ₄cは、各々独立に水素原子又は水酸基を表す。ただし、Ｒ₂c〜Ｒ₄cのうち少なくとも１つは水酸基を表す。
（ア）（Ａ）下記一般式（Ｉ_０）で表される部分構造を有する繰り返し単位と、下記一般式（II）で表される繰り返し単位を含有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、（Ｂ）活性光線または放射線の照射により酸を発生する化合物、を含有するポジ型フォトレジスト組成物。

式（Ｉ_０）中、ｍ1は１から６の整数を表す。Ｒ¹及びＲ²はそれぞれアルキル基もしくは環状アルキル基を表し、又はＲ¹とＲ²が互いに結合して環状アルキル基を形成してもよい。Ｒ³及びＲ⁴はそれぞれ水素原子、アルキル基もしくは環状アルキル基を表し、又はＲ³とＲ⁴が互いに結合して環状アルキル基を形成してもよい。Ｒ⁵〜Ｒ⁷はそれぞれアルキル基、環状アルキル基、アリール基、アリル基、トリアルキルシリル基又はトリアルキルシリルオキシ基を表す。

式（II）中、Ｙは水素原子、メチル基、シアノ基、塩素原子から選ばれる基を表す。Ｌ¹は単結合または２価の連結基を表す。Ｘ¹は−ＣＯ₂−、−Ｏ−、−ＣＯＮＨ−、−ＣＯＮ(Ｒ)−から選ばれる基を表す。ここでＲは置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。Ａはラクトン構造を含む基、ラクタム構造を含む基、置換基として−ＯＨ、−ＯＣＨ₃、−ＯＣＯＲａ、−ＯＣＯＯＲａ、−ＯＣＯＮＨＲａ、−ＯＣＯＮ(Ｒａ)(Ｒｂ)、−ＮＨＣＯＲａ、−ＮＨＣＯＯＲａ、−ＮＨＳＯ₂Ｒａ、−Ｎ(Ｒ)ＣＯＲａ、−Ｎ(Ｒ)ＣＯＯＲａ、−Ｎ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＯＲ、−ＣＯＮＨＲａ、−ＣＯＮＨＳＯ₂Ｒａ、−ＣＯＮ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＮ(Ｒａ)(Ｒｂ)、−ＣＮの群から選ばれる少なくとも１つの官能基を含有する飽和脂肪族基を表す。ここでＲ、Ｒａ、Ｒｂはそれぞれ独立に置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。
（イ）（Ａ）下記一般式（Ｉａ）及び（Ｉｂ）のうち少なくともいずれかで表される繰り返し単位と、下記一般式（Ｉｃ）で表される繰り返し単位を含有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂、（Ｂ）活性光線または放射線の照射により酸を発生する化合物を含有するポジ型フォトレジスト組成物。

式（Ｉａ）中、Ｙは水素原子、メチル基、シアノ基、塩素原子から選ばれる基を表す。Ｌは単結合または２価の連結基を表す。Ｒ¹〜Ｒ⁴はそれぞれ独立に水素原子、ＳｉＲ'(Ｒ'')(Ｒ''')、置換基としてＳｉＲ'(Ｒ'')(Ｒ''')を含んでも良いアルキル基を表す。但し、Ｒ¹〜Ｒ⁴の全てが水素原子になることはない。Ｒ'、Ｒ''、Ｒ'''はそれぞれ独立に直鎖または分岐を有するアルキル基、フェニル基、トリアルキルシリル基、トリアルキルシリルオキシ基を表す。

式（Ｉｂ）中、Ｘ¹は酸素原子、硫黄原子、炭素数１〜３のアルキレン基を表す。Ｌ、Ｒ¹〜Ｒ⁴、Ｒ'、Ｒ''、Ｒ'''は前記と同義である。

式（Ｉｃ）中、Ｙ、Ｌは前記式（Ｉａ）におけるのと同義である。Ｘ²は−ＣＯ₂−、−Ｏ−、−ＣＯＮＨ−、−ＣＯＮ(Ｒ)−から選ばれる基を表す。ここでＲは置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。Ａはラクトン構造を含む基、ラクタム構造を含む基、置換基として−ＯＣＨ₃、−ＯＣＯＲａ、−ＯＣＯＯＲａ、−ＯＣＯＮＨＲａ、−ＯＣＯＮ(Ｒａ)(Ｒｂ)、−ＮＨＣＯＲａ、−ＮＨＣＯＯＲａ、−ＮＨＳＯ₂Ｒａ、−Ｎ(Ｒ)ＣＯＲａ、−Ｎ(Ｒ)ＣＯＯＲａ、−Ｎ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＯＨ、−ＣＯＯＲ、−ＣＯＮＨＲａ、−ＣＯＮＨＳＯ₂Ｒａ、−ＣＯＮ(Ｒ)ＳＯ₂Ｒａ、−ＣＯＮ(Ｒａ)(Ｒｂ)、−ＣＮの群から選ばれる少なくとも１つの官能基を含有する飽和脂肪族基を表す。ここでＲ、Ｒａ、Ｒｂはそれぞれ独立に置換されていても良い炭素数１〜１０のアルキルまたはアリール基を表す。
＜７＞
更に、下記一般式（ＡＩ）で表される繰り返し単位を含有することを特徴とする上記＜５＞又は＜６＞に記載のポジ型感光性組成物。

一般式（ＡＩ）中、Ｒ_b0は、水素原子、ハロゲン原子、又は炭素数１〜４のアルキル基を表す。
Ａ’は、単結合、エーテル基、エステル基、カルボニル基、アルキレン基、又はこれらを組み合わせた２価の基を表す。
Ｂ₂は、一般式（Ｌｃ）又は一般式（Ｖ−１）〜（Ｖ−５）のうちのいずれかで示される基を表す。

一般式（Ｌｃ）中、Ｒａ₁，Ｒｂ₁，Ｒｃ₁，Ｒｄ₁，Ｒｅ₁は、各々独立に、水素原子又はアルキル基を表す。ｍ，ｎは各々独立に０〜３の整数を表し、ｍ＋ｎは、２以上６以下である。
一般式（Ｖ−１）〜（Ｖ−５）において、Ｒ_1b〜Ｒ_5bは、各々独立に、水素原子、アルキル基、シクロアルキル基、アルコキシ基、アルコキシカルボニル基、アルキルスルホニルイミノ基又はアルケニル基を表す。Ｒ_1b〜Ｒ_5bの内の２つは、結合して環を形成してもよい。
＜８＞
更に、（Ｄ）酸の作用により分解し、アルカリ現像液中での溶解度が増大する、分子量３０００以下の溶解阻止化合物を含有することを特徴とする上記＜１＞〜＜７＞のいずれかに記載のポジ型感光性組成物。
＜９＞
上記＜１＞〜＜８＞のいずれかに記載のポジ型感光性組成物により、膜を形成し、該膜を露光、現像する工程を含むことを特徴とするパターン形成方法。
＜１０＞
液浸液を介して露光することを特徴とする上記＜９＞に記載のパターン形成方法。
本発明は、上記＜１＞〜＜１０＞に係る発明であるが、以下、他の事項も含めて説明している。
（１）（Ａ）下記一般式（Ｉ）で表される基を有する繰り返し単位を有し、酸の作用によりアルカリ現像液に対する溶解度が増大する樹脂及び
（Ｂ）活性光線又は放射線の照射により酸を発生する化合物
を含有することを特徴とするポジ型感光性組成物。 <1>
(A) A repeating unit having a group represented by the following general formula (I) (excluding a repeating unit derived from a (meth) acrylate compound represented by the following general formula (MA)), the following general formula (pA A resin having a repeating unit represented by formula (AI) and a repeating unit represented by the following general formula (AI), and having increased solubility in an alkali developer by the action of an acid; and
(B) A positive photosensitive composition containing a compound that generates an acid upon irradiation with an actinic ray or radiation (except for the following (A) and (I)).

In general formula (I),
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.

Here, R represents a hydrogen atom, a halogen atom, or a linear or branched alkyl group having 1 to 4 carbon atoms. A plurality of R may be the same or different.
A is a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, or a urea group, or a combination of two or more groups Represents. Ra represents a group represented by any one of the following general formulas (pI) to (pVI).

In the formula, R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl group, and Z forms an alicyclic hydrocarbon group together with a carbon atom. Represents the atomic group necessary to do.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that at least one of R _{12 to} R ₁₄ , or Either R ₁₅ or R ₁₆ represents an alicyclic hydrocarbon group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{17 to} R ₂₁ Represents an alicyclic hydrocarbon group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{22 to} R ₂₅ Represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² and R ³ represent a hydrogen atom, or a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms, and R ² and R ³ are bonded to each other. In this case, R ² and R ³ represent a linear, branched or cyclic alkylene group having 2 to 15 carbon atoms. X is -CH ₂ -, - represents or -O-, or separated two -H groups together - CH ₂ CH _2. The dotted line is a norbornane ring, bicyclo [2.2.2] octane ring, 7-oxanorbornane ring, or a single bond that bonds the cyclohexane ring structure and the γ-butyrolactone ring structure, a divalent organic group, or between these two ring structures. Represents a structure sharing one or two constituent carbon atoms.
(A) (A) It contains a repeating unit having a partial structure represented by the following general formula (I ₀ ) and a repeating unit represented by the following general formula (II), and is soluble in an alkali developer by the action of an acid. A positive photoresist composition comprising: a resin having an increased number of ions; and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In the formula (I ₀ ), m1 represents an integer of 1 to 6. R ¹ and R ² each represents an alkyl group or a cyclic alkyl group, or R ¹ and R ² may be bonded to each other to form a cyclic alkyl group. R ³ and R ⁴ each represent a hydrogen atom, an alkyl group or a cyclic alkyl group, or R ³ and R ⁴ may be bonded to each other to form a cyclic alkyl group. R ^{5 to} R ⁷ each represents an alkyl group, a cyclic alkyl group, an aryl group, an allyl group, a trialkylsilyl group, or a trialkylsilyloxy group.

In formula (II), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L ¹ represents a single bond or a divalent linking group. X ¹ represents a group selected from —CO ₂ —, —O—, —CONH—, and —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OH, —OCH ₃ , —OCORa, —OCOORa, —OCONHRa, —OCON (Ra) (Rb), —NHCORa, —NHCOORa, —NHSO as substituents ₂ Ra, -N (R) CORa, -N (R) COORa, -N (R) SO ₂ Ra, -COOR, -CONHRa, -CONHSO ₂ Ra, -CON (R) SO ₂ Ra, -CON (Ra ) (Rb), a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.
(A) (A) a repeating unit represented by at least one of the following general formulas (Ia) and (Ib) and a repeating unit represented by the following general formula (Ic), A positive photoresist composition containing a resin having increased solubility in a developer and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In formula (Ia), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L represents a single bond or a divalent linking group. R ^{1 to} R ⁴ each independently represents a hydrogen atom, SiR ′ (R ″) (R ′ ″), or an alkyl group that may contain SiR ′ (R ″) (R ′ ″) as a substituent. . However, not all of R ^{1 to} R ⁴ are hydrogen atoms. R ′, R ″, and R ′ ″ each independently represent a linear or branched alkyl group, phenyl group, trialkylsilyl group, or trialkylsilyloxy group.

In the formula (Ib), X ¹ represents an oxygen atom, a sulfur atom, or an alkylene group having 1 to 3 carbon atoms. L, R ^{1 to} R ⁴ , R ′, R ″, and R ′ ″ are as defined above.

In formula (Ic), Y and L have the same meanings as in formula (Ia). X ² represents a group selected from —CO ₂ —, —O—, —CONH—, and —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A is a group containing a lactone structure, a group containing a lactam structure, -OCH _3, -OCORa as a substituent, -OCOORa, -OCONHRa, -OCON (Ra ) (Rb), - NHCORa, -NHCOORa, -NHSO 2 Ra, -N (R) CORa, -N ( R) COORa, -N (R) SO 2 Ra, -COOH, -COOR, -CONHRa, -CONHSO 2 Ra, -CON (R) SO 2 Ra, -CON (Ra ) (Rb), a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.
A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
B ₂ represents a group represented by any one of general formula (Lc) and general formulas (V-1) to (V-5).

In general formula (Lc), Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , and Re ₁ each independently represent a hydrogen atom or an alkyl group. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.
In the general formulas (V-1) to (V-5), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylsulfonylimino group, or an alkenyl group. Represents. Two of R _{1b to} R _5b may combine to form a ring.
<2>
(A) A repeating unit having a group represented by the following general formula (I), a repeating unit represented by the following general formula (AII), and a repeating unit represented by the following general formula (AI), and the action of an acid A resin whose solubility in an alkaline developer increases, and
(B) A positive photosensitive composition containing a compound that generates an acid upon irradiation with an actinic ray or radiation (except for the following (A) and (I)).

In general formula (I),
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.

In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group.
(A) (A) It contains a repeating unit having a partial structure represented by the following general formula (I ₀ ) and a repeating unit represented by the following general formula (II), and is soluble in an alkali developer by the action of an acid. A positive photoresist composition comprising: a resin having an increased number of ions; and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In the formula (I ₀ ), m1 represents an integer of 1 to 6. R ¹ and R ² each represents an alkyl group or a cyclic alkyl group, or R ¹ and R ² may be bonded to each other to form a cyclic alkyl group. R ³ and R ⁴ each represent a hydrogen atom, an alkyl group or a cyclic alkyl group, or R ³ and R ⁴ may be bonded to each other to form a cyclic alkyl group. R ^{5 to} R ⁷ each represents an alkyl group, a cyclic alkyl group, an aryl group, an allyl group, a trialkylsilyl group, or a trialkylsilyloxy group.

In formula (II), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L ¹ represents a single bond or a divalent linking group. X ¹ represents a group selected from —CO ₂ —, —O—, —CONH—, and —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OH, —OCH ₃ , —OCORa, —OCOORa, —OCONHRa, —OCON (Ra) (Rb), —NHCORa, —NHCOORa, —NHSO as substituents ₂ Ra, -N (R) CORa, -N (R) COORa, -N (R) SO ₂ Ra, -COOR, -CONHRa, -CONHSO ₂ Ra, -CON (R) SO ₂ Ra, -CON (Ra ) (Rb), a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.
(A) (A) a repeating unit represented by at least one of the following general formulas (Ia) and (Ib) and a repeating unit represented by the following general formula (Ic), A positive photoresist composition containing a resin having increased solubility in a developer and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In formula (Ia), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L represents a single bond or a divalent linking group. R ^{1 to} R ⁴ each independently represents a hydrogen atom, SiR ′ (R ″) (R ′ ″), or an alkyl group that may contain SiR ′ (R ″) (R ′ ″) as a substituent. . However, not all of R ^{1 to} R ⁴ are hydrogen atoms. R ′, R ″, and R ′ ″ each independently represent a linear or branched alkyl group, phenyl group, trialkylsilyl group, or trialkylsilyloxy group.

In the formula (Ib), X ¹ represents an oxygen atom, a sulfur atom, or an alkylene group having 1 to 3 carbon atoms. L, R ^{1 to} R ⁴ , R ′, R ″, and R ′ ″ are as defined above.

In formula (Ic), Y and L have the same meanings as in formula (Ia). X ² represents a group selected from —CO ₂ —, —O—, —CONH—, and —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A is a group containing a lactone structure, a group containing a lactam structure, -OCH _3, -OCORa as a substituent, -OCOORa, -OCONHRa, -OCON (Ra ) (Rb), - NHCORa, -NHCOORa, -NHSO 2 Ra, -N (R) CORa, -N ( R) COORa, -N (R) SO 2 Ra, -COOH, -COOR, -CONHRa, -CONHSO 2 Ra, -CON (R) SO 2 Ra, -CON (Ra ) (Rb), a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.
A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
B ₂ represents a group represented by any one of general formula (Lc) and general formulas (V-1) to (V-5).

In general formula (Lc), Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , and Re ₁ each independently represent a hydrogen atom or an alkyl group. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.
In the general formulas (V-1) to (V-5), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylsulfonylimino group, or an alkenyl group. Represents. Two of R _{1b to} R _5b may combine to form a ring.
<3>
The positive photosensitive composition as described in <1> or <2> above, wherein the repeating unit having a group represented by the general formula (I) is represented by the following general formula (I ′).

In general formula (I ′),
Ra ₁ represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.
<4>
In general formula (I) or general formula (I ′), L ₁ is a monocyclic or polycyclic (m + 1) valent group selected from cyclopentane, cyclohexane, norbornane, adamantane, tricyclodecane and tetracyclododecane. The positive photosensitive composition as described in any one of <1> to <3> above, which is an alicyclic hydrocarbon group.
<5>
(A) It has a repeating unit represented by any one of the following general formulas (1) to (3) and a repeating unit represented by the following general formula (AII), and the solubility in an alkali developer is increased by the action of an acid. Resin and
(B) A positive photosensitive composition containing a compound that generates an acid upon irradiation with an actinic ray or radiation (except for the following (A) and (I)).

Ra ₁ represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
Rb ₁ represents a substituent, and when a plurality of Rb ₁ are present, they may be the same or different.
n ₁ represents an integer of 0 to 3.

In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group.
(A) (A) It contains a repeating unit having a partial structure represented by the following general formula (I ₀ ) and a repeating unit represented by the following general formula (II), and is soluble in an alkali developer by the action of an acid. A positive photoresist composition comprising: a resin having an increased number of ions; and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In the formula (I ₀ ), m1 represents an integer of 1 to 6. R ¹ and R ² each represents an alkyl group or a cyclic alkyl group, or R ¹ and R ² may be bonded to each other to form a cyclic alkyl group. R ³ and R ⁴ each represent a hydrogen atom, an alkyl group or a cyclic alkyl group, or R ³ and R ⁴ may be bonded to each other to form a cyclic alkyl group. R ^{5 to} R ⁷ each represents an alkyl group, a cyclic alkyl group, an aryl group, an allyl group, a trialkylsilyl group, or a trialkylsilyloxy group.

In formula (II), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L ¹ represents a single bond or a divalent linking group. X ¹ represents a group selected from —CO ₂ —, —O—, —CONH—, and —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OH, —OCH ₃ , —OCORa, —OCOORa, —OCONHRa, —OCON (Ra) (Rb), —NHCORa, —NHCOORa, —NHSO as substituents ₂ Ra, -N (R) CORa, -N (R) COORa, -N (R) SO ₂ Ra, -COOR, -CONHRa, -CONHSO ₂ Ra, -CON (R) SO ₂ Ra, -CON (Ra ) (Rb), a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.
(A) (A) a repeating unit represented by at least one of the following general formulas (Ia) and (Ib) and a repeating unit represented by the following general formula (Ic), A positive photoresist composition containing a resin having increased solubility in a developer and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In formula (Ia), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L represents a single bond or a divalent linking group. R ^{1 to} R ⁴ each independently represents a hydrogen atom, SiR ′ (R ″) (R ′ ″), or an alkyl group that may contain SiR ′ (R ″) (R ′ ″) as a substituent. . However, not all of R ^{1 to} R ⁴ are hydrogen atoms. R ′, R ″, and R ′ ″ each independently represent a linear or branched alkyl group, phenyl group, trialkylsilyl group, or trialkylsilyloxy group.

In the formula (Ib), X ¹ represents an oxygen atom, a sulfur atom, or an alkylene group having 1 to 3 carbon atoms. L, R ^{1 to} R ⁴ , R ′, R ″, and R ′ ″ are as defined above.

In formula (Ic), Y and L have the same meanings as in formula (Ia). X ² represents a group selected from —CO ₂ —, —O—, —CONH—, —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A is a group containing a lactone structure, a group containing a lactam structure, -OCH _3, -OCORa as a substituent, -OCOORa, -OCONHRa, -OCON (Ra ) (Rb), - NHCORa, -NHCOORa, -NHSO 2 Ra, -N (R) CORa, -N ( R) COORa, -N (R) SO 2 Ra, -COOH, -COOR, -CONHRa, -CONHSO 2 Ra, -CON (R) SO 2 Ra, -CON (Ra ) (Rb), a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.
<6>
(A) a resin having a repeating unit represented by the following general formula (4) and a repeating unit represented by the following general formula (AII) and having increased solubility in an alkali developer by the action of an acid; and (B) A positive photosensitive composition comprising a compound capable of generating an acid upon irradiation with actinic rays or radiation (except for the following (A) and (B)).

Ra ₁ represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
Rb ₁ represents a substituent, and when a plurality of Rb ₁ are present, they may be the same or different.
n ₁ represents an integer of 0 to 3.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure represented by the following general formula (LC1-1) or (LC1-2).

n ₂ represents an integer of 0 to 3.
Rb ₂ represents a substituent.

In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group.
(A) (A) It contains a repeating unit having a partial structure represented by the following general formula (I ₀ ) and a repeating unit represented by the following general formula (II), and is soluble in an alkali developer by the action of an acid. A positive photoresist composition comprising: a resin having an increased number of ions; and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In the formula (I ₀ ), m1 represents an integer of 1 to 6. R ¹ and R ² each represents an alkyl group or a cyclic alkyl group, or R ¹ and R ² may be bonded to each other to form a cyclic alkyl group. R ³ and R ⁴ each represent a hydrogen atom, an alkyl group or a cyclic alkyl group, or R ³ and R ⁴ may be bonded to each other to form a cyclic alkyl group. R ^{5 to} R ⁷ each represents an alkyl group, a cyclic alkyl group, an aryl group, an allyl group, a trialkylsilyl group, or a trialkylsilyloxy group.

In formula (II), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L ¹ represents a single bond or a divalent linking group. X ¹ represents a group selected from —CO ₂ —, —O—, —CONH—, and —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OH, —OCH ₃ , —OCORa, —OCOORa, —OCONHRa, —OCON (Ra) (Rb), —NHCORa, —NHCOORa, —NHSO as substituents ₂ Ra, -N (R) CORa, -N (R) COORa, -N (R) SO ₂ Ra, -COOR, -CONHRa, -CONHSO ₂ Ra, -CON (R) SO ₂ Ra, -CON (Ra ) (Rb), a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.
(A) (A) a repeating unit represented by at least one of the following general formulas (Ia) and (Ib) and a repeating unit represented by the following general formula (Ic), A positive photoresist composition containing a resin having increased solubility in a developer and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In formula (Ia), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L represents a single bond or a divalent linking group. R ^{1 to} R ⁴ each independently represents a hydrogen atom, SiR ′ (R ″) (R ′ ″), or an alkyl group that may contain SiR ′ (R ″) (R ′ ″) as a substituent. . However, not all of R ^{1 to} R ⁴ are hydrogen atoms. R ′, R ″, and R ′ ″ each independently represent a linear or branched alkyl group, phenyl group, trialkylsilyl group, or trialkylsilyloxy group.

In the formula (Ib), X ¹ represents an oxygen atom, a sulfur atom, or an alkylene group having 1 to 3 carbon atoms. L, R ^{1 to} R ⁴ , R ′, R ″, and R ′ ″ are as defined above.

In formula (Ic), Y and L have the same meanings as in formula (Ia). X ² represents a group selected from —CO ₂ —, —O—, —CONH—, and —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A is a group containing a lactone structure, a group containing a lactam structure, -OCH _3, -OCORa as a substituent, -OCOORa, -OCONHRa, -OCON (Ra ) (Rb), - NHCORa, -NHCOORa, -NHSO 2 Ra, -N (R) CORa, -N ( R) COORa, -N (R) SO 2 Ra, -COOH, -COOR, -CONHRa, -CONHSO 2 Ra, -CON (R) SO 2 Ra, -CON (Ra ) (Rb), a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.
<7>
The positive photosensitive composition as described in <5> or <6> above, further comprising a repeating unit represented by the following general formula (AI).

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.
A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
B ₂ represents a group represented by any one of general formula (Lc) and general formulas (V-1) to (V-5).

In general formula (Lc), Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , and Re ₁ each independently represent a hydrogen atom or an alkyl group. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.
In the general formulas (V-1) to (V-5), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylsulfonylimino group, or an alkenyl group. Represents. Two of R _{1b to} R _5b may combine to form a ring.
<8>
Furthermore, (D) any one of the above items <1> to <7>, further comprising a dissolution inhibiting compound having a molecular weight of 3000 or less, which decomposes by the action of an acid and increases the solubility in an alkaline developer. The positive photosensitive composition as described.
<9>
A pattern forming method comprising a step of forming a film with the positive photosensitive composition according to any one of <1> to <8>, and exposing and developing the film.
<10>
The pattern forming method according to <9>, wherein the exposure is performed through an immersion liquid.
The present invention is an invention according to the above <1> to <10>, but is described below including other matters.
(1) (A) a resin having a repeating unit having a group represented by the following general formula (I) and having increased solubility in an alkali developer by the action of an acid; and (B) an acid upon irradiation with actinic rays or radiation. A positive photosensitive composition comprising a compound capable of generating odor.

In general formula (I),
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.

  (2) The positive photosensitive composition as described in (1), wherein the repeating unit having a group represented by the general formula (I) is represented by the following (I ′).

In general formula (I ′),
Ra ₁ represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.

(3) Further described in (1) or (2), further comprising (D) a dissolution inhibiting compound having a molecular weight of 3000 or less, which decomposes by the action of an acid and increases the solubility in an alkaline developer. A positive photosensitive composition.

  (4) A resin having a repeating unit represented by the following general formula (I ′).

In general formula (I ′),
Ra ₁ represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.

  (5) A polymerizable compound represented by the following general formula (I ″).

In general formula (I ''),
Ra ₁ represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.

  (6) A pattern forming method comprising a step of forming a film with the positive photosensitive composition according to any one of (1) to (3), and exposing and developing the film.

  According to the present invention, it is possible to provide a positive photosensitive composition having excellent resolving power and improved line edge roughness even in the formation of a fine pattern of 100 nm or less, and a pattern forming method using the same.

In addition, in the description of the group (atomic group) in this specification, the description which does not describe substitution and non-substitution includes what does not have a substituent and what has a substituent. . For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
Hereinafter, the present invention will be described in detail.

[1] Resin that increases the solubility in an alkaline developer by the action of an acid (component A)
The resin whose solubility in an alkaline developer is increased by the acid used in the positive photosensitive composition of the present invention has a repeating unit having a group represented by the following general formula (I).

In general formula (I),
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.

The monocyclic (m + 1) -valent alicyclic hydrocarbon group in the general formula (I) or L ₁ is preferably one having 4 to 8 carbon atoms, such as a cyclobutylene group, a cyclopentylene group, or cyclohexylene. Group, a cycloheptylene group, etc. are mentioned, More preferably, they are a cyclopentylene group and a cyclohexylene group.
The polycyclic (m + 1) -valent alicyclic hydrocarbon group in L ₁ is preferably one having 7 to 20 carbon atoms, for example, a hydrocarbon group having a bicyclo ring, tricyclo ring, tetracyclo ring, pentacyclo ring or the like. In which (m + 1) -valent linking group is formed. Specific examples include (m + 1) -valent linking groups obtained by removing (m + 1) hydrogen atoms from cyclic hydrocarbons such as norbornane, adamantane, tricyclodecane, and tetracyclododecane.
(M + 1) -valent alicyclic hydrocarbon group of L ₁ may have a substituent (Rb _1), preferred substituents (Rb _1), an alkyl group having 1 to 8 carbon atoms, carbon atoms A 4-7 cycloalkyl group, a C1-C8 alkoxy group, a C1-C8 alkoxycarbonyl group, a carboxyl group, a cyano group, a hydroxyl group, etc. are mentioned.

Examples of the divalent linking group for X ₁ include an —O— group, a —CO ₂ — group, an —S— group, an alkylene group, and a linking group in which a plurality of these are combined. An —O— group and a —CO ₂ — group are preferable.

As the group having a lactone structure in Lc ₁ , any group having a lactone structure can be used, but a group having a 5-membered ring or 6-membered ring lactone structure is preferred. The group having a lactone structure may or may not have a substituent (Rb ₂ ). Preferred substituents (Rb ₂ ) include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 1 to 8 carbon atoms, and a carboxyl group. , A cyano group, a hydroxyl group and the like.

Examples of preferable lactone structures in Lc ₁ include structures represented by the following general formulas (LC1-1) to (LC1-12). These may have the above-described substituent (Rb ₂ ).

In the general formulas (LC1-1) to (LC1-12),
n2 represents an integer of 0 to 3.
Rb ₂ is the above-described substituent, and when there are a plurality of Rb _{2 s} , they may be the same or different.

In the general formula (I), m is preferably 1.
When m is 2, two X _{1 s} may be the same or different, and two Lc _{1 s} may be the same or different.

In the general formula (I), the acid-decomposable resin of the present invention is linked by a linking group X ₁ capable of freely rotating an alicyclic hydrocarbon group L ₁ having a rigid structure and a group Lc ₁ having a lactone structure. By having such a structure, the hydrophilicity of the lactone group is sufficiently expressed, and the image performance is improved.

  As the repeating unit having a group represented by the general formula (I), a (meth) acrylic acid ester derivative having a group represented by the general formula (I), a (meth) acrylamide derivative, a vinyl ether derivative, an olefin derivative, styrene The repeating unit by a derivative etc. is mentioned, Preferably it is a repeating unit by a (meth) acrylic acid ester derivative, More preferably, it is a repeating unit represented by the following general formula (I ').

In general formula (I ′),
Ra ₁ represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.

In L ₁ in the general formula _{(I '), X 1,} Lc 1 and m have the same meanings as in L _1, X _1, Lc ₁ and m in the general formula (I).

The alkyl group of Ra ₁ and Ra ₂ is preferably an alkyl group having 1 to 4 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, and a t-butyl group. Can do. The alkyl group of Ra ₁ and Ra ₂ may have a substituent such as a halogen atom.
The acyl group of Ra ₂ is preferably an acyl group having 1 to 8 carbon atoms, and examples thereof include a formyl group, an acetyl group, a propionyl group, a butyryl group, a pareryl group, a pivaloyl group, and a benzoyl group.

Ra ₁ is preferably a hydrogen atom or a methyl group.

  Hereinafter, preferred repeating units among the repeating units represented by the general formula (I ′) are listed, but the present invention is not limited thereto.

In the above general formula,
Ra _1, X _1, Lc ₁ is a general formula in Ra ₁ to _{(I '), X 1,} Lc 1 synonymous. Lc ₁ preferably has the lactone structures (Lc1-1) to (Lc1-12) described above.
Rb ₁ represents the above-mentioned substituent, and when a plurality of Rb ₁ are present, they may be the same or different.
n1 represents the integer of 0-3.

  Specific examples of the repeating unit represented by the general formula (I ′) are shown below, but the present invention is not limited thereto.

In the above specific examples, Ra ₂ represents a hydrogen atom or a methyl group.

The acid-decomposable resin (A) is obtained by copolymerizing a monomer (polymerizable compound) having a group represented by the general formula (I) with another monomer.
As the monomer having a group represented by the general formula (I), a monomer represented by the following general formula (I ″) is preferable.

_{'In, Ra 1, L 1, X} 1, Lc 1 and m have the general formula (I formula (I') 'in Ra _{1 to), L 1, X 1,} Lc 1 and m as defined It is.

  Among the monomers represented by the general formula (I ″), monomers represented by the following general formula are more preferable.

In the above general formula,
Ra _1, X _1, Lc ₁ is a general formula in Ra ₁ to _{(I '), X 1,} Lc 1 synonymous. Lc ₁ preferably has the lactone structures (Lc1-1) to (Lc1-12) described above.
Rb ₁ represents the above-mentioned substituent, and when a plurality of Rb ₁ are present, they may be the same or different.
n1 represents the integer of 0-3.

  Specific examples of the monomer represented by the general formula (I ″) are shown below, but the present invention is not limited thereto.

In the above specific examples, Ra ₂ represents a hydrogen atom or a methyl group.

The resin used in the positive photosensitive composition of the present invention is a group capable of decomposing with an acid (hereinafter also referred to as “acid-decomposable group”) on the main chain or side chain of the resin, or both the main chain and side chain. It is resin which has.
A preferred group that can be decomposed with an acid is a group in which the hydrogen atom of the —COOH group is substituted with a group capable of leaving with an acid.
The acid-decomposable group is preferably a cumyl ester group, an enol ester group, an acetal ester group, a tertiary alkyl ester group or the like. More preferably, it is a tertiary alkyl ester group.

  Resins that are decomposed by the action of an acid to increase the solubility in an alkali developer include a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the following general formulas (pI) to (pVI) and the following general formula: A resin containing at least one selected from the group of repeating units represented by (II-AB) is preferred.

(Wherein R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl group, and Z represents an alicyclic hydrocarbon group together with a carbon atom. Represents the atomic group necessary to form.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that at least one of R _{12 to} R ₁₄ , or Either R ₁₅ or R ₁₆ represents an alicyclic hydrocarbon group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{17 to} R ₂₁ Represents an alicyclic hydrocarbon group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{22 to} R ₂₅ Represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring. )

In formula (II-AB):
R ₁₁ ', R _12' each independently represent a hydrogen atom, a cyano group, a halogen atom, or an alkyl group.
Z ′ represents an atomic group for forming an alicyclic structure containing two bonded carbon atoms (C—C).

  The general formula (II-AB) is more preferably the following general formula (II-A) or general formula (II-B).

In formulas (II-A) and (II-B):
R ₁₃ ′ to R ₁₆ ′ each independently represents a hydrogen atom, a halogen atom, a cyano group, —COOH, —C
OOR _{5 represents} a group decomposable by the action of an acid, —C (═O) —XA′—R ₁₇ ′, an alkyl group or a cyclic hydrocarbon group.
Wherein, R ₅ represents an alkyl group, cyclic hydrocarbon group, or -Y group shown below.
X represents an oxygen atom, a sulfur atom, -NH -, - NHSO ₂ - or an -NHSO ₂ NH-.
A ′ represents a single bond or a divalent linking group.
Further, at least two of R ₁₃ ′ to R ₁₆ ′ may be bonded to form a ring. n represents 0 or 1.
R ₁₇ ′ represents —COOH, —COOR ₅ , —CN, a hydroxyl group, an alkoxy group, —CO—NH—R ₆ , —CO—NH—SO ₂ —R ₆ or the following —Y group.
R ₆ represents an alkyl group or a cyclic hydrocarbon group.
The -Y group;

(In the —Y group, R ₂₁ ′ to R ₃₀ ′ each independently represents a hydrogen atom or an alkyl group. A and b represent 1 or 2.)

In the general formulas (pI) to (pVI), the alkyl group in R _{12 to} R ₂₅ may be substituted or unsubstituted, and is a linear or branched alkyl group having 1 to 4 carbon atoms. Represents. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group.
Further, the further substituent of the alkyl group includes an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an acyl group, an acyloxy group, a cyano group, a hydroxyl group, A carboxy group, an alkoxycarbonyl group, a nitro group, etc. can be mentioned.

The alicyclic hydrocarbon group in R _{11 to} R _{25 or} the alicyclic hydrocarbon group formed by Z and a carbon atom may be monocyclic or polycyclic. Specific examples include groups having a monocyclo, bicyclo, tricyclo, tetracyclo structure or the like having 5 or more carbon atoms. The carbon number is preferably 6-30, and particularly preferably 7-25. These alicyclic hydrocarbon groups may have a substituent.

  Preferred examples of the alicyclic hydrocarbon group include an adamantyl group, a noradamantyl group, a decalin residue, a tricyclodecanyl group, a tetracyclododecanyl group, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Group, cyclodecanyl group, and cyclododecanyl group. More preferred are an adamantyl group, a decalin residue, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, and a cyclododecanyl group.

Examples of the substituent for these alicyclic hydrocarbon groups include an alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group, and an alkoxycarbonyl group. The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group or a butyl group, more preferably a methyl group, an ethyl group, a propyl group or an isopropyl group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. The alkyl group and alkoxy group may further have a substituent. Examples of further substituents on the alkyl group and alkoxy group include a hydroxyl group, a halogen atom, and an alkoxy group.

The structures represented by the general formulas (pI) to (pVI) in the resin can be used for protecting alkali-soluble groups. Examples of the alkali-soluble group include various groups known in this technical field.
Specific examples include a carboxylic acid group, a sulfonic acid group, a phenol group, and a thiol group, and a carboxylic acid group and a sulfonic acid group are preferable.
As the alkali-soluble group protected by the structure represented by the general formulas (pI) to (pVI) in the above resin, the hydrogen atom of the carboxyl group is preferably substituted with the structure represented by the general formula (pI) to (PVI). Structure.

  As the repeating unit having an alkali-soluble group protected by the structure represented by the general formulas (pI) to (pVI), a repeating unit represented by the following general formula (pA) is preferable.

Here, R represents a hydrogen atom, a halogen atom, or a linear or branched alkyl group having 1 to 4 carbon atoms. A plurality of R may be the same or different.
A is a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, or a urea group, or a combination of two or more groups Represents. The alkylene group may further have a substituent.
Ra represents any group of the above formulas (pI) to (pVI).

  The repeating unit represented by the general formula (pA) is most preferably a repeating unit of 2-alkyl-2-adamantyl (meth) acrylate and dialkyl (1-adamantyl) methyl (meth) acrylate.

  Specific examples of the repeating unit represented by the general formula (pA) are shown below.

In the general formula (II-AB), R ₁₁ ′ and R ₁₂ ′ each independently represent a hydrogen atom, a cyano group, a halogen atom, or an alkyl group.
Z ′ represents an atomic group for forming an alicyclic structure containing two bonded carbon atoms (C—C).

The R ₁₁ ', R _12' As the halogen atom in include a chlorine atom, a bromine atom, a fluorine atom, an iodine atom.
The alkyl group for R ₁₁ ′ and R ₁₂ ′ is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably a linear or branched alkyl group having 1 to 6 carbon atoms. And more preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, or a t-butyl group.

  The alkyl group may further have a substituent. Examples of the further substituent of the alkyl group include a hydroxyl group, a halogen atom, a carboxyl group, an alkoxy group, an acyl group, a cyano group, and an acyloxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the acyl group include a formyl group and an acetyl group, and examples of the acyloxy group include an acetoxy group.

The atomic group for forming the alicyclic structure of Z ′ is an atomic group that forms a repeating unit of an alicyclic hydrocarbon in a resin, and in particular, forms a repeating unit of a bridged alicyclic hydrocarbon. An atomic group for forming a bridged alicyclic structure is preferred.
Examples of the skeleton of the alicyclic hydrocarbon formed include the same alicyclic hydrocarbon groups as R _{11 to} R _{25 in} the general formulas (pI) to (pVI).

The alicyclic hydrocarbon skeleton may have a substituent. Examples of such a substituent include R ₁₃ ′ to R ₁₆ ′ in the general formula (II-A) or (II-B).
Among the repeating units having the bridged alicyclic hydrocarbon, the repeating unit represented by the general formula (II-A) or (II-B) is more preferable.

In the acid-decomposable resin in the invention, the acid-decomposable group, the -C (= O) -X-A' -R 17 ' may be included in, Z in formula (II-AB)' May be included as a substituent.
The structure of the acid-decomposable group is represented by —C (═O) —X ₁ —R ₀ .
In the formula, R ₀ is a tertiary alkyl group such as t-butyl group or t-amyl group, isobornyl group, 1-ethoxyethyl group, 1-butoxyethyl group, 1-isobutoxyethyl group, 1-cyclohexyloxy. 1-alkoxyethyl group such as ethyl group, 1-methoxymethyl group, alkoxymethyl group such as 1-ethoxymethyl group, 3-oxoalkyl group, tetrahydropyranyl group, tetrahydrofuranyl group, trialkylsilyl ester group, 3- An oxocyclohexyl ester group, a 2-methyl-2-adamantyl group, a mevalonic lactone residue and the like can be mentioned. X ₁ has the same meaning as X above.

Examples of the halogen atom in R ₁₃ ′ to R ₁₆ ′ include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.

The alkyl group in R ₅ , R ₆ , R ₁₃ ′ to R ₁₆ ′, R ₂₁ ′ to R ₃₀ ′ is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably carbon. A linear or branched alkyl group of several to six, more preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, or a t-butyl group. is there.

Examples of the cyclic hydrocarbon group in R ₅ , R ₆ and R ₁₃ ′ to R ₁₆ ′ include a cyclic alkyl group and a bridged hydrocarbon group, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, 2- List methyl-2-adamantyl group, norbornyl group, boronyl group, isobornyl group, tricyclodecanyl group, dicyclopentenyl group, nobornane epoxy group, menthyl group, isomenthyl group, neomenthyl group, tetracyclododecanyl group, etc. Can do.
Examples of the ring formed by combining at least two of R ₁₃ ′ to R ₁₆ ′ include rings having 5 to 12 carbon atoms such as cyclopentene, cyclohexene, cycloheptane, and cyclooctane.

Examples of the alkoxy group for R ₁₇ ′ include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

The alkyl group, cyclic hydrocarbon group, and alkoxy group may further have a substituent. Examples of further substituents on the alkyl group, cyclic hydrocarbon group, and alkoxy group include a hydroxyl group, a halogen atom, a carboxyl group, an alkoxy group, an acyl group, a cyano group, an acyloxy group, an alkyl group, and a cyclic hydrocarbon group. it can. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group. Examples of the acyl group include a formyl group and an acetyl group. Examples thereof include an acetoxy group.
Examples of the alkyl group and cyclic hydrocarbon group include those listed above.

  The divalent linking group for A ′ is one or two selected from the group consisting of an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, and a urea group. Combinations of the above groups can be mentioned. The alkylene group may have a substituent.

  In the acid-decomposable resin according to the present invention, the group capable of decomposing by the action of an acid is a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the general formula (pI) to general formula (pVI), It can be contained in at least one repeating unit among the repeating unit represented by the formula (II-AB) and the repeating unit of the copolymerization component described later.

Various substituents of R ₁₃ ′ to R ₁₆ ′ in the general formula (II-A) or the general formula (II-B) are atomic groups for forming an alicyclic structure in the general formula (II-AB). Or it becomes a substituent of atomic group Z for forming a bridged alicyclic structure.

  Specific examples of the repeating unit represented by the general formula (II-A) or the general formula (II-B) include the following, but the present invention is not limited to these specific examples.

  The acid-decomposable resin of the present invention can have a repeating unit having a lactone group in addition to the repeating unit having a group represented by the general formula (I). Preferably, it is a repeating unit having a group having a lactone structure represented by any of the following general formula (Lc) or the following general formulas (V-1) to (V-5), and the group having a lactone structure is a main chain. It may be directly bonded to.

In general formula (Lc), Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , and Re ₁ each independently represent a hydrogen atom or an alkyl group. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.

In the general formulas (V-1) to (V-5), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylsulfonylimino group, or an alkenyl group. Represents. Two of R _{1b to} R _5b may combine to form a ring.

R _{1 to} Re ₁ alkyl groups in general formula (Lc) and R _{1b to} R _5b alkyl groups, alkoxy groups, alkoxycarbonyl groups, alkyl groups in general formulas (V-1) to (V-5) Examples of the alkyl group in the sulfonylimino group include linear and branched alkyl groups, which may have a substituent.

As the repeating unit having a group having a lactone structure represented by general formula (Lc) or any one of general formulas (V-1) to (V-5), the above general formula (II-A) or (II- B) wherein at least one of R ₁₃ ′ to R ₁₆ ′ has a group represented by general formula (Lc) or general formula (V-1) to (V-5) (for example, R in —COOR ₅ ) ₅ represents a group represented by general formula (Lc) or general formulas (V-1) to (V-5)), or a repeating unit represented by the following general formula (AI).

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.
Examples of the halogen atom for R _b0 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R _b0 is preferably a hydrogen atom.
A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
B ₂ represents a group represented by any one of general formula (Lc) and general formulas (V-1) to (V-5).

  Specific examples of the repeating unit having a group having a lactone structure are shown below, but the present invention is not limited thereto.

  The acid-decomposable resin of the present invention may contain a repeating unit having a group represented by the following general formula (VII).

In general formula (VII), R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group.

  The group represented by the general formula (VII) is preferably a dihydroxy form or a monohydroxy form, and more preferably a dihydroxy form.

As the repeating unit having a group represented by the general formula (VII), at least one of R ₁₃ ′ to R ₁₆ ′ in the general formula (II-A) or (II-B) is the above general formula (VII ) (For example, R _{5 in} —COOR ₅ represents a group represented by the general formula (VII)), or a repeating unit represented by the following general formula (AII). it can.

In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group. _{Two of} R ₂ c to R ₄ c are preferably hydroxyl groups.

Although the specific example of the repeating unit which has a structure represented by general formula (AII) below is given, it is not limited to these.

The acid-decomposable resin of the present invention may have a repeating unit having an alkali-soluble group.
The alkali-soluble group is preferably a carboxyl group, specifically, a repeating unit in which a carboxyl group is directly bonded to the main chain of methacrylic acid, acrylic acid, etc., and a carboxyl by adamantane-3-carboxylic acid-1- (meth) acrylate, etc. Examples include a repeating unit in which a group is bonded to the main chain via an alicyclic linking group.

  The acid-decomposable resin of the present invention may have a repeating unit represented by the following general formula (VIII).

In the general formula (VIII), Z ₂ represents —O— or —N (R ₄₁ ) —. Here, R ₄₁ represents a hydrogen atom, a hydroxyl group, an alkyl group, or —OSO ₂ —R ₄₂ . R ₄₂ represents an alkyl group, a cycloalkyl group or a camphor residue. The alkyl group may be substituted with a halogen atom or the like.

  Specific examples of the repeating unit represented by the general formula (VIII) include the following [I′-1] to [I′-7], but the present invention is not limited to these specific examples. .

  In addition to the above repeating structural units, the acid-decomposable resin of the present invention has dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and general required properties of resist, resolving power, heat resistance, and sensitivity. Various repeating structural units can be contained for the purpose of adjusting the above.

Examples of such repeating structural units include, but are not limited to, repeating structural units corresponding to the following monomers.
Thereby, the performance required for the acid-decomposable resin, in particular,
(1) Solubility in coating solvent,
(2) Film formability (glass transition point),
(3) Alkali developability,
(4) Membrane slip (hydrophobic, alkali-soluble group selection),
(5) Adhesion of unexposed part to substrate,
(6) Dry etching resistance,
Etc. can be finely adjusted.
As such a monomer, for example, a compound having one addition polymerizable unsaturated bond selected from acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, etc. Etc.

  In addition, any addition-polymerizable unsaturated compound that can be copolymerized with monomers corresponding to the above various repeating structural units may be copolymerized.

  In acid-decomposable resins, the molar ratio of each repeating structural unit is the resist dry etch resistance, standard developer suitability, substrate adhesion, resist profile, and general resist performance required for resolving power, heat resistance, and sensitivity. It is set appropriately in order to adjust etc.

Preferred embodiments of the acid-decomposable resin of the present invention include the following.
(1) Containing a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the general formulas (pI) to (pVI) (side chain type)
(2) Containing repeating units represented by general formula (II-AB) (main chain type)
However, in (2), for example, the following can be further mentioned.
(3) A repeating unit represented by the general formula (II-AB), a maleic anhydride derivative and a (meth) acrylate structure (hybrid type)

In the acid-decomposable resin, the content of the repeating unit having a group represented by the general formula (I) is preferably 10 to 70 mol%, more preferably 20 to 65 mol%, still more preferably 25 in all repeating units. ˜50 mol%.
In the acid-decomposable resin, the content of the repeating unit having an acid-decomposable group is preferably 10 to 70 mol%, more preferably 20 to 65 mol%, still more preferably 25 to 60 mol% in all repeating structural units. is there.
In the acid-decomposable resin, the content of the repeating unit having a partial structure containing an alicyclic hydrocarbon represented by general formulas (pI) to (pVI) is preferably 20 to 70 mol% in all repeating structural units, More preferably, it is 24-65 mol%, More preferably, it is 28-60 mol%.
In the acid-decomposable resin, the content of the repeating unit represented by the general formula (II-AB) is preferably 10 to 60 mol%, more preferably 15 to 55 mol%, still more preferably 20 in all repeating structural units. ˜50 mol%.

In addition, the content of the repeating structural unit based on the monomer of the further copolymer component in the resin can also be appropriately set according to the performance of the desired resist. 99 mol% with respect to the total number of moles of the repeating structural unit having a partial structure containing the alicyclic hydrocarbon represented by (pVI) and the repeating unit represented by the above general formula (II-AB) The following is preferable, More preferably, it is 90 mol% or less, More preferably, it is 80 mol% or less.
When the composition of the present invention is for ArF exposure, the resin preferably has no aromatic group from the viewpoint of transparency to ArF light.

The acid-decomposable resin used in the present invention can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, monomer species are charged into a reaction vessel in a batch or in the course of reaction, and this is added to a reaction solvent, for example, cyclic ethers such as tetrahydrofuran and 1,4-dioxane, methyl ethyl ketone, methyl isobutyl. Ketones, ketones such as cyclohexanone, and the composition of the present invention such as propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether, which will be described later, are uniformly dissolved in a solvent, and then inert gas such as nitrogen or argon. Polymerization is started using a commercially available radical initiator (azo initiator, peroxide, etc.) as necessary under an atmosphere. If desired, an initiator is added or added in portions, and after completion of the reaction, it is put into a solvent and a desired polymer is recovered by a method such as powder or solid recovery. The concentration of the reaction is 10% by mass or more, preferably 15% by mass or more, and more preferably 20% by mass or more. The reaction temperature is 10 ° C to 150 ° C, preferably 30 ° C to 120 ° C, more preferably 50-100 ° C.

The repeating structural units represented by the above specific examples may be used singly or in combination.
In the present invention, the resins may be used alone or in combination.

The weight average molecular weight of the resin according to the present invention is preferably 1,000 to 200,000, more preferably 3,000 to 20,000, as a polystyrene converted value by the GPC method. By setting the weight average molecular weight to 1,000 to 200,000, deterioration of heat resistance and dry etching resistance can be prevented, and developability is deteriorated, or viscosity is increased and film forming property is deteriorated. Can be prevented.
The molecular weight distribution is usually 1 to 5, preferably 1 to 4, more preferably 1 to 3. The smaller the molecular weight distribution, the better the resolution and the resist shape, and the smoother the sidewall of the resist pattern, the better the roughness.

  In the positive photosensitive composition of the present invention, the blending amount of all the resins according to the present invention in the entire composition is preferably 40 to 99.99% by mass, more preferably 50 to 99.97, based on the total solid content. % By mass.

[2] Compound that generates acid upon irradiation with actinic rays or radiation (component B)
The positive photosensitive composition of the present invention contains a compound that generates an acid upon irradiation with actinic rays or radiation.
Examples of such photoacid generators include photoinitiators for photocationic polymerization, photoinitiators for photoradical polymerization, photodecolorants for dyes, photochromic agents, actinic rays used in microresists, etc. Known compounds that generate an acid upon irradiation with radiation and mixtures thereof can be appropriately selected and used.

  Examples thereof include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, and o-nitrobenzyl sulfonates.

  Further, a group that generates an acid upon irradiation with these actinic rays or radiation, or a compound in which a compound is introduced into the main chain or side chain of the polymer, for example, US Pat. No. 3,849,137, German Patent No. 3914407. JP, 63-26653, JP, 55-164824, JP, 62-69263, JP, 63-146038, JP, 63-163452, JP, 62-153853, The compounds described in JP-A 63-146029 can be used.

Furthermore, compounds capable of generating an acid by light described in US Pat. No. 3,779,778, European Patent 126,712 and the like can also be used.

  Among the compounds that can be used and decomposed by irradiation with actinic rays or radiation, preferred compounds include compounds represented by the following general formulas (ZI), (ZII), and (ZIII). it can.

In the above general formula (ZI),
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
X ⁻ represents a non-nucleophilic anion, preferably sulfonate anion, carboxylate anion, bis (alkylsulfonyl) amide anion, tris (alkylsulfonyl) methide anion, BF ₄ —, PF ₆ —, SbF ₆ — and the like. Preferably, it is an organic anion containing a carbon atom.

  Preferable organic anions include organic anions represented by the following formula.

Rc ₁ represents an organic group.

Examples of the organic group for Rc ₁ include those having 1 to 30 carbon atoms, and preferably an alkyl group, a cycloalkyl group, an aryl group, or a plurality thereof is a single bond, —O—, —CO ₂ —, —S—. , —SO ₃ —, —SO ₂ N (Rd ₁ ) — and the like.
Rd ₁ represents a hydrogen atom or an alkyl group.
Rc ₃ , Rc ₄ and Rc ₅ each independently represents an organic group.
Examples of the organic group of Rc ₃ , Rc ₄ , and Rc ₅ are preferably the same as the preferable organic group in Rc ₁ , and most preferably a perfluoroalkyl group having 1 to 4 carbon atoms.
Rc ₃ and Rc ₄ may combine to form a ring.
Examples of the group formed by combining Rc ₃ and Rc ₄ include an alkylene group and an arylene group. A perfluoroalkylene group having 2 to 4 carbon atoms is preferred.
The organic group of Rc _1, Rc ₃ -Rc _5, most preferably 1-position fluorine atom or an alkyl group substituted with a fluoroalkyl group, a phenyl group substituted with a fluorine atom or a fluoroalkyl group. By having a fluorine atom or a fluoroalkyl group, the acidity of the acid generated by light irradiation is increased and the sensitivity is improved.

The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.
Two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group.
The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).
Specific examples of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include corresponding groups in the compounds (Z1-1), (Z1-2) and (Z1-3) described later.

In addition, the compound which has two or more structures represented by general formula (Z1) may be sufficient. For example, the general formula at least one of R ₂₀₁ to R ₂₀₃ of a compound represented by (Z1) is at least one bond with structure of R ₂₀₁ to R ₂₀₃ of another compound represented by formula (Z1) It may be a compound.

  As more preferred (Z1) component, compounds (Z1-1), (Z1-2), and (Z1-3) described below can be exemplified.

Compound (Z1-1) is at least one of the aryl groups R ₂₀₁ to R ₂₀₃ in formula (Z1), arylsulfonium compound, i.e., a compound having arylsulfonium as a cation.
Arylsulfonium compound, all of R ₂₀₁ to R ₂₀₃ may be an aryl group or a part of R ₂₀₁ to R ₂₀₃ is an aryl group and the remainder may be an alkyl group or a cycloalkyl group.
Examples of the arylsulfonium compound include triarylsulfonium compounds, diarylalkylsulfonium compounds, aryldialkylsulfonium compounds, diarylcycloalkylsulfonium compounds, and aryldicycloalkylsulfonium compounds.
The aryl group of the arylsulfonium compound is preferably a phenyl group, a naphthyl group, or an indole residue, more preferably a phenyl group or an indole residue. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.
The alkyl group that the arylsulfonium compound has as necessary is preferably a linear or branched alkyl group having 1 to 15 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, sec- Examples thereof include a butyl group and a t-butyl group.
The cycloalkyl group that the arylsulfonium compound has as necessary is preferably a cycloalkyl group having 3 to 15 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.
Aryl group, alkyl group of R ₂₀₁ to R _203, cycloalkyl group, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 14 carbon atoms) , An alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, or a phenylthio group may be substituted. Preferred substituents are straight chain, branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, straight chain, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, and most preferably They are a C1-C4 alkyl group and a C1-C4 alkoxy group. The substituent may be substituted with any one of the three R _{201 to} R ₂₀₃ , or may be substituted with all three. When R _{201 to} R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

Next, the compound (Z1-2) will be described.
Compound (Z1-2) is a compound in the case where R _{201 to} R ₂₀₃ in formula (Z1) each independently represents an organic group not containing an aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.
The organic group having no aromatic ring as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.
R _{201 to} R ₂₀₃ are each independently preferably an alkyl group, a cycloalkyl group, a linear, branched, or cyclic 2-oxoalkyl group, an alkoxycarbonylmethyl group, an allyl group, or a vinyl group, and more preferably a straight group. A chain, branched, cyclic 2-oxoalkyl group, alkoxycarbonylmethyl group, most preferably a linear, branched 2-oxoalkyl group.

The alkyl group as R ₂₀₁ to R ₂₀₃ may be linear, it may be either branched, preferably a straight-chain or branched alkyl group having 1 to 10 carbon atoms, e.g., methyl group, ethyl group, propyl group Butyl group and pentyl group.
The cycloalkyl group as R ₂₀₁ to R ₂₀₃ is preferably a cycloalkyl group having 3 to 10 carbon atoms, e.g., cyclopentyl, cyclohexyl group and a norbornyl group.
The 2-oxoalkyl group as R _{201 to} R ₂₀₃ may be linear, branched or cyclic, and is preferably a group having> C═O at the 2-position of the above alkyl group or cycloalkyl group Can be mentioned.
The alkoxy group in the alkoxycarbonylmethyl group as R ₂₀₁ to R _203, preferably may be mentioned alkoxy groups having 1 to 5 carbon atoms (a methoxy group, an ethoxy group, a propoxy group, a butoxy group, pentyloxy group).
R _{201 to} R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

  The compound (Z1-3) is a compound represented by the following general formula (Z1-3), and is a compound having a phenacylsulfonium salt structure.

In general formula (ZI-3),
R _{1c to} R _5c each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, or a halogen atom.
R _6c and R _7c each independently represents a hydrogen atom, an alkyl group or a cycloalkyl group.
Rx and Ry each independently represents an alkyl group, a cycloalkyl group, a 2-oxoalkyl group, an alkoxycarbonylmethyl group, an allyl group, or a vinyl group.
Any two or more of R _{1c to} R _5c , R _6c and R _7c, and R _x and R _y may be bonded to each other to form a ring structure, and this ring structure includes an oxygen atom, a sulfur atom, An ester bond or an amide bond may be included. Examples of the group formed by combining any two or more of R _{1c to} R _5c , R _6c and R _7c, and R _x and R _y include a butylene group and a pentylene group.
Zc ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as X ^{− in} the general formula (Z1).

The alkyl group as R _{1c to} R _7c may be either linear or branched, preferably a linear or branched alkyl group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms. And a straight-chain or branched alkyl group, for example, a methyl group, an ethyl group, a straight-chain or branched propyl group, a straight-chain or branched butyl group, or a straight-chain or branched pentyl group.
The cycloalkyl group as R _{1c to} R _7c is preferably a cycloalkyl group having 3 to 8 carbon atoms, and examples thereof include a cyclopentyl group and a cyclohexyl group.
The alkoxy group as R _{1c to} R _{5c may} be linear, branched or cyclic, for example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 5 carbon atoms. (For example, methoxy group, ethoxy group, linear or branched propoxy group, linear or branched butoxy group, linear or branched pentoxy group), C3-C8 cyclic alkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group) ).
Preferably, any one of R _{1c to} R _5c is a linear or branched alkyl group, a cycloalkyl group, or a linear, branched or cyclic alkoxy group, and more preferably the sum of the carbon number of R _1c to R _5c is 2 ~ 15. Thereby, solvent solubility improves more and generation | occurrence | production of a particle is suppressed at the time of a preservation | save.

_Examples of the alkyl group and cycloalkyl group as R _x and R _y include the same alkyl groups and cycloalkyl groups as R _{1c to} R _7c .
Examples of the 2-oxoalkyl group include a group having> C═O at the 2-position of the alkyl group or cycloalkyl group as R _{1c to} R _7c .
Examples of the alkoxy group in the alkoxycarbonylmethyl group include the same alkoxy groups as R _{1c to} R _5c .

R _x and R _y are preferably an alkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more.

In formula (ZII), (ZIII), R 204 ~R 207 each independently represents an aryl group, an alkyl group or a cycloalkyl group.
Phenyl group and a naphthyl group are preferred as the aryl group of R ₂₀₄ to R _207, more preferably a phenyl group.
The alkyl group as R ₂₀₄ to R ₂₀₇ may be linear, it may be either branched, preferably a straight-chain or branched alkyl group having 1 to 10 carbon atoms, e.g., methyl group, ethyl group, propyl group Butyl group and pentyl group.
The cycloalkyl group as R ₂₀₄ to R ₂₀₇ is preferably a cycloalkyl group having 3 to 10 carbon atoms. For example, a cyclopentyl group, a cyclohexyl group, and a norbornyl group can be mentioned.
R ₂₀₄ to R ₂₀₇ may have a substituent. The R ₂₀₄ to R ₂₀₇ are substituents which may have, for example, an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (e.g., 6 carbon atoms 15), alkoxy groups (for example, having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, phenylthio groups and the like.
X ⁻ represents a non-nucleophilic anion, and examples thereof include the same as the non-nucleophilic anion of X ^{− in} formula (I).

  Examples of the compound that generates an acid upon irradiation with actinic rays or radiation that can be used further include compounds represented by the following general formulas (ZIV), (ZV), and (ZVI).

In general formulas (ZIV) to (ZVI), Ar ₃ and Ar ₄ each independently represents an aryl group.
R ₂₀₆ , R ₂₀₇ and R ₂₀₈ each independently represents an alkyl group or an aryl group.
A represents an alkylene group, an alkenylene group or an arylene group.

  Of the compounds that generate an acid upon irradiation with actinic rays or radiation, compounds represented by general formulas (ZI) to (ZIII) are more preferable.

  Among the compounds that decompose upon irradiation with actinic rays or radiation to generate an acid, examples of particularly preferable compounds are listed below.

  (B) The addition amount of the compound of a component is 0.1-20 mass% normally with respect to the total solid of a composition, Preferably it is 0.5-20 mass%, More preferably, it is 1-10 mass%.

[3] (C) Basic compound The positive photosensitive composition of the present invention preferably further contains a basic compound.
As the basic compound, an organic amine, a basic ammonium salt, a basic sulfonium salt, a basic iodonium salt, or the like may be used as long as it does not deteriorate sublimation or resist performance. The basic compound is a component having an action of controlling a diffusion phenomenon in a resist film of an acid generated from an acid generator by exposure and suppressing an undesirable chemical reaction in a non-exposed region. By blending such a basic compound, the storage stability of the positive photosensitive composition obtained by controlling the diffusion phenomenon of the acid generated from the acid generator upon exposure in the resist film can be improved. While further improving the resolution, it is possible to suppress changes in the line width of the resist pattern due to fluctuations in the holding time (PED) from exposure to development processing, and a composition having excellent process stability can be obtained.

  As the basic compound, organic amines can be used, for example, primary, secondary, and tertiary aliphatic amines, aromatic amines, heterocyclic amines, and nitrogen-containing compounds having a carboxy group. And nitrogen-containing compounds having a sulfonyl group, nitrogen-containing compounds having a hydroxyl group, nitrogen-containing compounds having a hydroxyphenyl group, alcoholic nitrogen-containing compounds, amide derivatives, imide derivatives, nitrogen-containing compounds having a cyano group, and the like.

  As aliphatic amines, methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, tert-butylamine, pentylamine, tert-amylamine, cyclopentylamine, hexylamine, cyclohexylamine, Heptylamine, octylamine, nonylamine, decylamine, dodecylamine, cetylamine, methylenediamine, ethylenediamine, tetraethylenepentamine, dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, di-n-butylamine, diisobutylamine, di -Sec-butylamine, dipentylamine, dicyclopentylamine, dihexylamine, dicyclohexylamine, diheptylamine , Dioctylamine, dinonylamine, didecylamine, didodecylamine, dicetylamine, N, N-dimethylmethylenediamine, N, N-dimethylethylenediamine, N, N-dimethyltetraethylenepentamine, trimethylamine, triethylamine, tri-n-propylamine , Triisopropylamine, tri-n-butylamine, triisobutylamine, tri-sec-butylamine, tripentylamine, tricyclopentylamine, trihexylamine, tricyclohexylamine, triheptylamine, trioctylamine, trinonylamine, trinonylamine Decylamine, tridodecylamine, tricetylamine, N, N, N ′, N′-tetramethylmethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, N, N N ', N'-tetramethyl-tetraethylenepentamine, dimethylethylamine, methylethylpropylamine, benzylamine, phenethylamine, benzyldimethylamine, and the like.

Aromatic amines and heterocyclic amines include aniline derivatives such as aniline, N-methylaniline, N-ethylaniline, N-propylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, ethylaniline, propylaniline, trimethylaniline, 2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 2,4-dinitroaniline, 2,6-dinitroaniline, 3,5-dinitroaniline, N, N-dimethyltoluidine, etc.), diphenyl (p-tolyl) amine, methyldiphenylamine, triphenylamine, phenylenediamine, naphthylamine, diaminonaphthalene, pyrrole derivatives (eg pyrrole, 2H-pyrrole, 1-methylpyrrole, 2,4 -Dimethylpyro , 2,5-dimethylpyrrole, N-methylpyrrole, etc.), oxazole derivatives (eg oxazole, isoxazole etc.), thiazole derivatives (eg thiazole, isothiazole etc.), imidazole derivatives (eg imidazole, 4-methylimidazole, 4 -Methyl-2-phenylimidazole, etc.), pyrazole derivatives, furazane derivatives, pyrroline derivatives (eg pyrroline, 2-methyl-1-pyrroline etc.), pyrrolidine derivatives (eg pyrrolidine, N-methylpyrrolidine, pyrrolidinone, N-methylpyrrolidone etc.) ), Imidazoline derivatives, imidazolidine derivatives, pyridine derivatives (eg pyridine, methylpyridine, ethylpyridine, propylpyridine, butylpyridine, 4- (1-butylpentyl) pyridine, dimethylpyridine) Trimethylpyridine, triethylpyridine, phenylpyridine, 3-methyl-2-phenylpyridine, 4-tert-butylpyridine, diphenylpyridine, benzylpyridine, methoxypyridine, butoxypyridine, dimethoxypyridine, 1-methyl-2-pyridone, 4- Pyrrolidinopyridine, 1-methyl-4-phenylpyridine, 2- (1-ethylpropyl) pyridine, aminopyridine, dimethylaminopyridine, etc.), pyridazine derivatives, pyrimidine derivatives, pyrazine derivatives, pyrazoline derivatives, pyrazolidine derivatives, piperidine derivatives, Piperazine derivatives, morpholine derivatives, indole derivatives, isoindole derivatives, 1H-indazole derivatives, indoline derivatives, quinoline derivatives (eg quinoline, 3-quinolinecarbonitrile) Etc.), isoquinoline derivatives, cinnoline derivatives, quinazoline derivatives, quinoxaline derivatives, phthalazine derivatives, purine derivatives, pteridine derivatives, carbazole derivatives, phenanthridine derivatives, acridine derivatives, phenazine derivatives, 1,10-phenanthroline derivatives, adenine derivatives, adenosine derivatives Guanine derivatives, guanosine derivatives, uracil derivatives, uridine derivatives and the like.

  Examples of the nitrogen-containing compound having a carboxy group include aminobenzoic acid, indolecarboxylic acid, amino acid derivatives (for example, nicotinic acid, alanine, arginine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, glycylleucine, leucine, methionine, phenylalanine. , Threonine, lysine, 3-aminopyrazine-2-carboxylic acid, methoxyalanine) and the like.

  Examples of the nitrogen-containing compound having a sulfonyl group include 3-pyridinesulfonic acid and pyridinium p-toluenesulfonate.

  Examples of the nitrogen-containing compound having a hydroxyl group include 2-hydroxypyridine, aminocresol, 2,4-quinolinediol, 3-indolemethanol hydrate, monoethanolamine, diethanolamine, triethanolamine, N-ethyldiethanolamine, N, N- Diethylethanolamine, triisopropanolamine, 2,2′-iminodiethanol, 2-aminoethanol, 3-amino-1-propanol, 4-amino-1-butanol, 4- (2-hydroxyethyl) morpholine, 2- (2-hydroxyethyl) pyridine, 1- (2-hydroxyethyl) piperazine, 1- [2- (2-hydroxyethoxy) ethyl] piperazine, piperidine ethanol, 1- (2-hydroxyethyl) pyrrolidine, 1- (2 -Hydroxyethyl ) -2-pyrrolidinone, 3-piperidino-1,2-propanediol, 3-pyrrolidino-1,2-propanediol, 8-hydroxyeurolidine, 3-quinuclidinol, 3-tropanol, 1-methyl-2 -Pyrrolidine ethanol, 1-aziridine ethanol, N- (2-hydroxyethyl) phthalimide, N- (2-hydroxyethyl) isonicotinamide and the like are exemplified.

  Examples of amide derivatives include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide and the like.

  Examples of imide derivatives include phthalimide, succinimide, maleimide and the like.

Specific examples of the nitrogen-containing compound having a cyano group include 3- (diethylamino) propiononitrile, N, N-bis (2-hydroxyethyl) -3-aminopropiononitrile, N, N-bis (2- Acetoxyethyl) -3-aminopropiononitrile, N, N-bis (2-formyloxyethyl) -3-aminopropiononitrile, N, N-bis (2-methoxyethyl) -3-aminopropiononitrile, N, N-bis [2- (methoxymethoxy) ethyl] -3-aminopropiononitrile, methyl N- (2-cyanoethyl) -N- (2-methoxyethyl) -3-aminopropionate, N- (2 -Cyanoethyl) -N- (2-hydroxyethyl) -3-aminopropionic acid methyl, N- (2-acetoxyethyl) -N- (2-cyanoethyl) Methyl 3-aminopropionate, N- (2-cyanoethyl) -N-ethyl-3-aminopropiononitrile, N- (2-cyanoethyl) -N- (2-hydroxyethyl) -3-aminopropiononitrile, N- (2-acetoxyethyl) -N- (2-cyanoethyl) -3-aminopropiononitrile, N- (2-cyanoethyl) -N- (2-formyloxyethyl) -3-aminopropiononitrile, N -(2-cyanoethyl) -N- (2-methoxyethyl) -3-aminopropiononitrile, N- (
2-cyanoethyl) -N- [2- (methoxymethoxy) ethyl] -3-aminopropiononitrile, N- (2-cyanoethyl) -N- (3-hydroxy-1-propyl) -3-aminopropiononitrile N- (3-acetoxy-1-propyl) -N- (2-cyanoethyl) -3-aminopropiononitrile, N- (2-cyanoethyl) -N- (3-formyloxy-1-propyl) -3 -Aminopropiononitrile, N- (2-cyanoethyl) -N-tetrahydrofurfuryl-3-aminopropiononitrile, N, N-bis (2-cyanoethyl) -3-aminopropiononitrile, diethylaminoacetonitrile, N, N-bis (2-hydroxyethyl) aminoacetonitrile, N, N-bis (2-acetoxyethyl) aminoacetonitrile N, N-bis (2-formyloxyethyl) aminoacetonitrile, N, N-bis (2-methoxyethyl) aminoacetonitrile, N, N-bis [2- (methoxymethoxy) ethyl] aminoacetonitrile, N-cyanomethyl -N- (2-methoxyethyl) -3-aminopropionic acid methyl, N-cyanomethyl-N- (2-hydroxyethyl) -3-aminopropionic acid methyl, N- (2-acetoxyethyl) -N-cyanomethyl- Methyl 3-aminopropionate, N-cyanomethyl-N- (2-hydroxyethyl) aminoacetonitrile, N- (2-acetoxyethyl) -N- (cyanomethyl) aminoacetonitrile, N-cyanomethyl-N- (2-formyloxy Ethyl) aminoacetonitrile, N-cyanomethyl-N- (2-metho Siethyl) aminoacetonitrile, N-cyanomethyl-N- [2- (methoxymethoxy) ethyl] aminoacetonitrile, N- (cyanomethyl) -N- (3-hydroxy-1-propyl) aminoacetonitrile, N- (3-acetoxy- 1-propyl) -N- (cyanomethyl) aminoacetonitrile, N-cyanomethyl-N- (3-formyloxy-1-propyl) aminoacetonitrile, N, N-bis (cyanomethyl) aminoacetonitrile, 1-pyrrolidinepropiononitrile, 1-piperidinepropiononitrile, 4-morpholinepropiononitrile, 1-pyrrolidineacetonitrile, 1-piperidineacetonitrile, 4-morpholineacetonitrile, cyanomethyl 3-diethylaminopropionate, N, N-bis (2-hydroxye Til) -3-aminopropionate cyanomethyl, N, N-bis (2-acetoxyethyl) -3-aminopropionate cyanomethyl, N, N-bis (2-formyloxyethyl) -3-aminopropionate cyanomethyl, N , N-bis (2-methoxyethyl) -3-aminopropionic acid cyanomethyl, N, N-bis [2- (methoxymethoxy) ethyl] -3-aminopropionic acid cyanomethyl, 3-diethylaminopropionic acid (2-cyanoethyl) N, N-bis (2-hydroxyethyl) -3-aminopropionic acid (2-cyanoethyl), N, N-bis (2-acetoxyethyl) -3-aminopropionic acid (2-cyanoethyl), N, N -Bis (2-formyloxyethyl) -3-aminopropionic acid (2-cyanoethyl), N, N-bis 2-methoxyethyl) -3-aminopropionic acid (2-cyanoethyl), N, N-bis [2- (methoxymethoxy) ethyl] -3-aminopropionic acid (2-cyanoethyl), cyanomethyl 1-pyrrolidinepropionate, Examples include cyanomethyl 1-piperidinepropionate, cyanomethyl 4-morpholinepropionate, 1-pyrrolidinepropionic acid (2-cyanoethyl), 1-piperidinepropionic acid (2-cyanoethyl), 4-morpholinepropionic acid (2-cyanoethyl). .

As the nitrogen-containing basic compound, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5.4.0] -7-undecene, 1,4-diazabicyclo [ 2.2.2] Octane, 4-dimethylaminopyridine, 1-naphthylamine, piperidines, hexamethylenetetramine, imidazoles, hydroxypyridines, pyridines, anilines, hydroxyalkylanilines, 4,4′-diaminodiphenyl ether , Pyridinium p-toluenesulfonate, 2,4,6-trimethylpyridinium p-toluenesulfonate, tetramethylammonium p-toluenesulfonate, and tetrabutylammonium lactate, triethylamine, tributylamine, tripentylamine, tri-n- Octyl Amine, tri-i-octylamine, tris (ethylhexyl) amine, tridecylamine, tridodecylamine, tri-n-propylamine,
Tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, cyclohexyldimethylamine, Methyldicyclohexylamine, ethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 4,4′-diamino Benzophenone, 4,4′-diaminodiphenylamine, 2,2-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 2- (4-aminophenyl) 2- (3-hydroxyphenyl) propane, 2- (4-aminophenyl) -2- (4-hydroxyphenyl) propane, 1,4-bis [1- (4-aminophenyl) -1-methylethyl] benzene, 1,3-bis [1- (4- Aminophenyl) -1-methylethyl] benzene, bis (2-dimethylaminoethyl) ether, bis (2-diethylaminoethyl) ether, N, N, N ′, N′-tetrakis (2-hydroxypropyl) ethylenediamine, tri Tri (cyclo) alkylamines such as cyclohexylamine; aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, 4-nitroaniline, diphenylamine, triphenyl Aromatic amines such as amine, naphthylamine, 2,6-diisopropylaniline, polyethylene Nimine, polyallylamine, 2-dimethylaminoethylacrylamide polymer, Nt-butoxycarbonyldi-n-octylamine, Nt-butoxycarbonyldi-n-nonylamine, Nt-butoxycarbonyldi-n- Decylamine, Nt-butoxycarbonyldicyclohexylamine, Nt-butoxycarbonyl-1-adamantylamine, Nt-butoxycarbonyl-N-methyl-1-adamantylamine, N, N-di-t-butoxycarbonyl- 1-adamantylamine, N, N-di-t-butoxycarbonyl-N-methyl-1-adamantylamine, Nt-butoxycarbonyl-4,4′-diaminodiphenylmethane, N, N′-di-t-butoxy Carbonyl hexamethylenediamine, N, N, N′N′-tetra- -Butoxycarbonylhexamethylenediamine, N, N'-di-t-butoxycarbonyl-1,7-diaminoheptane, N, N'-di-t-butoxycarbonyl-1,8-diaminooctane, N, N'- Di-t-butoxycarbonyl-1,9-diaminononane, N, N′-di-t-butoxycarbonyl-1,10-diaminodecane, N, N′-di-t-butoxycarbonyl-1,12-diaminododecane N, N′-di-t-butoxycarbonyl-4,4′-diaminodiphenylmethane, Nt-butoxycarbonylbenzimidazole, Nt-butoxycarbonyl-2-methylbenzimidazole, Nt-butoxycarbonyl- 2-phenylbenzimidazole, formamide, N-methylformamide, N, N-dimethylformamide, aceto Amide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone, N-methylpyrrolidone, urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3, Imidazoles such as 3-tetramethylurea, 1,3-diphenylurea, tri-n-butylthiourea, imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, benzimidazole, 2-phenylbenzimidazole; pyridine 2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, 2-methyl-4-phenylpyridine, nicotine, nicotinic acid, nicotinamide, quinoline 4-hydroxy Pyrazines such as norine, 8-oxyquinoline, acridine; piperazines such as piperazine, 1- (2-hydroxyethyl) piperazine, pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, 3-piperidino-1 , 2-propanediol, morpholine, 4-methylmorpholine, 1,4-dimethylpiperazine, 1,4-diazabicyclo [2.2.2] octane.

Among these, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5.4.0] -7-undecene, 1,4-diazabicyclo [2.2.2] Octane, 4-dimethylaminopyridine, 1-naphthylamine, piperidine, 4-hydroxypiperidine, 2,2,6,6-tetramethyl-4-hydroxypiperidine, hexamethylenetetramine, imidazoles, hydroxypyridines, pyridines, 4 , 4'-diaminodiphenyl ether, triethylamine, tributylamine, tripentylamine, tri-n-octylamine, tris (ethylhexyl) amine, tridodecylamine, N, N-di-hydroxyethylaniline, N-hydroxyethyl-N- Organic amines such as ethylaniline are particularly preferred.

  The nitrogen-containing basic compounds can be used alone or in combination of two or more, more preferably in combination of two or more.

The positive resist composition of the present invention preferably further contains an ammonium salt compound. Specific examples of the ammonium salt include the following compounds, but are not limited thereto.
Specifically, ammonium hydroxide, ammonium triflate, ammonium pentaflate, ammonium heptaflate, ammonium nonaflate, ammonium undecaflate, ammonium tridecaflate, ammonium pentadecaflate, ammonium methylcarboxylate, ammonium ethylcarboxylate, Ammonium propyl carboxylate, ammonium butyl carboxylate, ammonium heptyl carboxylate, ammonium hexyl carboxylate, ammonium octyl carboxylate, ammonium nonyl carboxylate, ammonium decyl carboxylate, ammonium undecyl carboxylate, ammonium dodecadecyl carboxylate, ammonium salt Decyl carboxylate, ammonium tetradecyl carboxylate, ammonium pentadecyl carboxylate, ammonium hexadecyl carboxylate, ammonium heptadecyl carboxylate, ammonium octadecyl carboxylate and the like.

That is, as the ammonium hydroxide, specifically, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrapentylammonium hydroxide, tetrahexylammonium hydroxide, Tetraheptylammonium hydroxide, methyltrioctylammonium hydroxide, tetraoctylammonium hydroxide, didecyldimethylammonium hydroxide, tetrakisdecylammonium hydroxide, dodecyltrimethylammonium hydroxide, dodecylethyldimethylammonium hydroxide, didodecyldimethylammonium hydroxy And tridodecylmethylammonium Droxide, myristylmethylammonium hydroxide, dimethylditetradecylammonium hydroxide, hexadecyltrimethylammonium hydroxide, octadecyltrimethylammonium hydroxide, dimethyldioctadecylammonium hydroxide, tetraoctadecylammonium hydroxide, diallyldimethylammonium hydroxide, (2 -Chloroethyl) -trimethylammonium hydroxide, (2-bromoethyl) trimethylammonium hydroxide, (3-bromopropyl) -trimethylammonium hydroxide, (3-bromopropyl) triethylammonium hydroxide, glycidyltrimethylammonium hydroxide, choline hydroxy (R)-(+)-(3-chloro-2- (Droxypropyl) trimethylammonium hydroxide, (S)-(−)-(3-chloro-2-hydroxypropyl) -trimethylammonium hydroxide, (3-chloro-2-hydroxypropyl) -trimethylammonium hydroxide, ( 2-aminoethyl) -trimethylammonium hydroxide, hexamethonium hydroxide, decamethonium hydroxide, 1-azoniaproperan hydroxide, petronium hydroxide, 2-chloro-1,3-dimethyl-2-imidazoli Examples thereof include nium hydroxide and 3-ethyl-2-methyl-2-thiazolinium hydroxide.

  The total amount of the organic amine and basic ammonium salt is usually 0.001 to 10% by mass, preferably 0.01 to 5% by mass, based on the solid content of the positive photosensitive composition. . By setting it as 0.001-10 mass%, the effect of addition of the said component can be acquired, and the tendency for the fall of a sensitivity and the developability of a non-exposed part to deteriorate can be prevented.

[4] (D) A dissolution inhibiting compound having a molecular weight of 3000 or less (hereinafter also referred to as a “dissolution inhibiting compound”) that is decomposed by the action of an acid to increase the solubility in an alkaline developer.
As a dissolution inhibiting compound having a molecular weight of 3000 or less, which is decomposed by the action of an acid to increase the solubility in an alkaline developer, it does not decrease the transmittance of 220 nm or less, and is described in Proceeding of SPIE, 2724,355 (1996). An alicyclic or aliphatic compound containing an acid-decomposable group is preferred, such as a cholic acid derivative containing an acid-decomposable group. Examples of the acid-decomposable group and alicyclic structure are the same as those described for the acid-decomposable resin.
The molecular weight of the dissolution inhibiting compound in the present invention is 3000 or less, preferably 300 to 3000, and more preferably 500 to 2500.

  The addition amount of the dissolution inhibiting compound is preferably 1 to 30% by mass, more preferably 2 to 20% by mass, based on the solid content of the positive photosensitive composition.

  Specific examples of the dissolution inhibiting compound are shown below, but are not limited thereto.

[5] Fluorine-based and / or silicon-based surfactant The positive photosensitive composition of the present invention further includes a fluorine-based and / or silicon-based surfactant (fluorine-based surfactant and silicon-based surfactant, fluorine It is preferable that one or two or more surfactants containing both atoms and silicon atoms are contained.
When the positive photosensitive composition of the present invention contains fluorine and / or a silicon-based surfactant, adhesion and development with good sensitivity and resolution when using an exposure light source of 250 nm or less, particularly 220 nm or less. A resist pattern with few defects can be provided.
Examples of these fluorine and / or silicon surfactants include, for example, JP-A No. 62-36663, JP-A No. 61-226746, JP-A No. 61-226745, JP-A No. 62-170950, JP 63-34540 A, JP 7-230165 A, JP 8-62834 A, JP 9-54432 A, JP 9-5988 A, JP 2002-277862 A, US Patent Nos. 5,405,720, 5,360,692, 5,529,881, 5,296,330, 5,436,098, 5,576,143, 5,294,511, 5,824,451 Surfactant can be mentioned, The following commercially available surfactant can also be used as it is.
Examples of commercially available surfactants that can be used include EFTOP EF301 and EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430 and 431 (manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171, F173, F176, F189, and R08. (Dainippon Ink Chemical Co., Ltd.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (Asahi Glass Co., Ltd.), Troisol S-366 (Troy Chemical Co., Ltd.), etc. Fluorine type surfactant or silicon type surfactant can be mentioned. Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

In addition to the known surfactants described above, the surfactant is derived from a fluoroaliphatic compound produced by a telomerization method (also called telomer method) or an oligomerization method (also called oligomer method). A surfactant using a polymer having a fluoroaliphatic group can be used. The fluoroaliphatic compound can be synthesized by the method described in JP-A-2002-90991.
As the polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferable and distributed irregularly. Or may be block copolymerized. Examples of the poly (oxyalkylene) group include a poly (oxyethylene) group, a poly (oxypropylene) group, a poly (oxybutylene) group, and the like, and a poly (oxyethylene, oxypropylene, and oxyethylene group). A unit having different chain lengths in the same chain length, such as a block link) or poly (block link of oxyethylene and oxypropylene) may be used. Further, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate (or methacrylate) is 2
Not only the original copolymer but also a ternary system or more obtained by simultaneously copolymerizing monomers having two or more different fluoroaliphatic groups or two or more different (poly (oxyalkylene)) acrylates (or methacrylates). A copolymer may be used.
Examples of commercially available surfactants include Megafac F178, F-470, F-473, F-475, F-476, and F-472 (Dainippon Ink Chemical Co., Ltd.). Further, a copolymer of an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxyalkylene)) acrylate (or methacrylate), an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxy) (Ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate) copolymer, acrylate (or methacrylate) and (poly (oxyalkylene)) acrylate having C ₈ F ₁₇ groups (or Copolymer of acrylate (or methacrylate), (poly (oxyethylene)) acrylate (or methacrylate), and (poly (oxypropylene)) acrylate (or methacrylate) having a C ₈ F ₁₇ group List union It can be.

  The amount of fluorine and / or silicon surfactant used is preferably 0.0001 to 2% by mass, more preferably 0.001 to 1% by mass, based on the total amount of the positive photosensitive composition (excluding the solvent). It is.

[6] Organic solvent The positive photosensitive composition of the present invention is used by dissolving each component in a predetermined organic solvent.
Examples of the organic solvent that can be used include ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl. Ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N -Dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran, etc.

In the present invention, the organic solvent may be used alone or in combination, but a solvent having a hydroxyl group in the structure, a solvent having an ester or lactone structure in the structure, and a solvent having a ketone structure in the structure It is preferable to use a mixed solvent in which two or more selected from the above are mixed. Thereby, the generation of particles during storage of the resist solution can be reduced.
Examples of the solvent having a hydroxyl group include ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethyl lactate, and the like. Propylene glycol monomethyl ether and ethyl lactate are particularly preferred.
Examples of the solvent having an ester or lactone structure include propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, γ-butyrolactone, butyl acetate, and the like. Among these, propylene glycol monomethyl ether acetate, ethyl ethoxy Propionate is particularly preferred, and propylene glycol monomethyl ether acetate is most preferred.
Examples of the solvent having a ketone structure include 2-heptanone and cyclohexanone, with cyclohexanone being preferred.
A preferable combination of the mixed solvent is a combination of a solvent having a hydroxyl group and a solvent having an ester structure, or a combination of a solvent having a ketone structure and a solvent having an ester structure.

The mixing ratio (mass) of the solvent having a hydroxyl group and the solvent having an ester structure is usually 1/99 to 99/1, preferably 5/95 to 95/5, more preferably 20/80 to 80/20, particularly. Preferably it is 20 / 80-60 / 40.
The mixing ratio (mass) of the solvent having a ketone structure and the solvent having an ester structure is usually 1/99 to 99/1, preferably 5/95 to 95/5, more preferably 20/80 to 80/20, Particularly preferred is 20/80 to 60/40.

<Other additives>
If necessary, the positive photosensitive composition of the present invention may further contain a dye, a plasticizer, a surfactant other than the above components, a photosensitizer, a compound that promotes solubility in a developer, and the like. Can do.
The dissolution accelerating compound for the developer that can be used in the present invention is a low molecular weight compound having a molecular weight of 1,000 or less and having two or more phenolic OH groups or one or more carboxy groups. When it has a carboxy group, an alicyclic or aliphatic compound is preferable.
A preferable addition amount of these dissolution promoting compounds is 2 to 50% by mass, and more preferably 5 to 30% by mass with respect to the resin of the component (B). By making the addition amount 2 to 50% by mass, it is possible to prevent development residue from deteriorating and deformation of the pattern during development.

Such a phenol compound having a molecular weight of 1000 or less can be easily synthesized by those skilled in the art with reference to the methods described in, for example, JP-A-4-1222938, JP-A-2-28531, US Pat. can do.
Specific examples of alicyclic or aliphatic compounds having a carboxyl group include carboxylic acid derivatives having a steroid structure such as cholic acid, deoxycholic acid, lithocholic acid, adamantane carboxylic acid derivatives, adamantane dicarboxylic acid, cyclohexane carboxylic acid, cyclohexane Examples thereof include, but are not limited to, dicarboxylic acids.

In the present invention, a surfactant other than the fluorine-based and / or silicon-based surfactant may be added. Specifically, nonionic interfaces such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan aliphatic esters, polyoxyethylene sorbitan aliphatic esters, etc. Mention may be made of activators.
These surfactants may be added alone or in some combination.

≪How to use≫
The positive photosensitive composition of the present invention is used by dissolving each component in a predetermined organic solvent, preferably the mixed solvent, and applying the solution on a predetermined support as follows.
For example, the positive photosensitive composition is applied on a substrate (for example, silicon / silicon dioxide coating) used for manufacturing a precision integrated circuit device by an appropriate application method such as a spinner or a coater.
After the application, actinic rays and radiation are irradiated through a predetermined mask, followed by baking and development. In this way, a good pattern can be obtained. Examples of the actinic ray include infrared light, visible light, ultraviolet light, far ultraviolet light, X-ray, electron beam, etc., but preferably far ultraviolet light having a wavelength of 250 nm or less, more preferably 220 nm or less, specifically Specifically, KrF excimer laser (248 nm), ArF excimer laser (193 nm), F2 excimer laser (157 nm), X-ray, electron beam, etc., ArF excimer laser and F2 excimer laser are most preferable. In the present invention, X-rays and electron beams are also included in the actinic rays.

In the development step, an alkaline developer is used as follows. As an alkaline developer of the resist composition, inorganic hydroxides such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, primary amines such as ethylamine and n-propylamine, Secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcohol amines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide and the like Alkaline aqueous solutions such as quaternary ammonium salts, cyclic amines such as pyrrole and pihelidine can be used.
Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline developer.
The alkali concentration of the alkali developer is usually from 0.1 to 20% by mass.
The pH of the alkali developer is usually from 10.0 to 15.0.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to this.
In addition, Example 5, 7 and 8 shall be read as a reference example.

Synthesis Example 1 (Synthesis of Monomer (I-1))
10 g of the following carboxylic acid monomer (IsomerMixture) and 5.3 g of N, N-diisopropylethylamine were dissolved in 100 ml of acetone, and 11.4 g of α-bromo-γ-butyrolactone was added dropwise to the solution under ice cooling. After reacting at room temperature for 24 hours, the reaction solution was concentrated to 30 ml. To this, 300 ml of ethyl acetate was added, and this was washed twice with 100 ml of distilled water, and with a saturated aqueous solution of sodium bicarbonate and saturated brine. The organic phase was dried over magnesium sulfate and concentrated to give the crude product. When this was purified by column chromatography, 8.7 g of monomer (I-1) was obtained.
300 MHz- ¹ H-NMR (CDCl3)
δ1.1 to 2.8 (m, 15H), δ4.2-4.4 (m, 1H), δ4.4-4.5
(M, 1H), δ 5.0 (bs, 1H), δ 5.35-5.5 (m, 1H), δ 5.5 (s, 1H), δ 6.0 (s, 1H)

Synthesis Example 2 (Synthesis of resin (P1))
Under a nitrogen stream, 1.38 g of propylene glycol monomethyl ether acetate and 0.92 g of propylene glycol monomethyl ether were placed in a three-necked flask and heated to 80 ° C. To this, 3.04 g of monomer (I-1), 1.01 g of dihydroxyadamantane methacrylate, 1.57 g of isoadamantyl methacrylate, 0.18 g of methacrylic acid, 12.42 g of propylene glycol monomethyl ether acetate, polymerization initiator V-601 (sum) A product obtained by dissolving 6 mol% of Kopure Pharmaceutical Co., Ltd. in 8.28 g of propylene glycol monomethyl ether with respect to the monomer was added dropwise over 6 hours. After completion of dropping, the reaction was further carried out at 80 ° C. for 2 hours. The reaction solution was allowed to cool and then poured into 270 ml of hexane / 30 ml of ethyl acetate, and the precipitated powder was collected by filtration and dried to obtain 4.6 g of Resin (P1). The obtained resin (P1) had a weight average molecular weight of 10320 and a dispersity (Mw / Mn) of 2.10.
Resins (P2) to (P14) and the resins (Q1) and (Q2) used in Comparative Examples were also synthesized by the same dropping polymerization method.
Hereinafter, the structures, weight average molecular weights, and dispersities of the acid-decomposable resins (P1) to (P14) used in the examples and the resins (Q1) and (Q2) used in the comparative examples are shown.

Examples 1 to 14 and Comparative Example 1
<Resist preparation>
The components shown in Table 1 below were dissolved in a solvent to prepare a solution having a solid content concentration of 8% by mass, and this was filtered through a 0.1 μm polyethylene filter to prepare a positive resist composition. The prepared positive resist composition was evaluated by the following method, and the results are shown in Table 1.

  Hereinafter, the abbreviations in Table 1 are as follows.

N-1: trioctylamine N-2: 2,6-diisopropylaniline N-3: N-phenyldiethanolamine N-4: diazabicyclo [4.3.0] nonene N-5: dicyclohexylmethylamine N-6: 2 , 4,5-Triphenylimidazole N-7: 4-dimethylaminopyridine

W-1; Megafuck F176 (Dainippon Ink Chemical Co., Ltd.) (fluorine)
W-2; Megafuck R08 (Dainippon Ink Chemical Co., Ltd.)
(Fluorine and silicon)
W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.)
(Silicon)
W-4; Troisol S-366 (manufactured by Troy Chemical Co., Ltd.)

SL-1: cyclohexanone SL-2; propylene glycol monomethyl ether acetate SL-3: ethyl lactate SL-4: propylene glycol monomethyl ether SL-5: γ-butyrolactone In Table 1, the ratio when a plurality of solvents are used Is the mass ratio.

D-1; t-butyl lithocholic acid

<Resist evaluation>
ARC29A manufactured by Brewer Science Co., Ltd. was uniformly applied to a silicon wafer with a spin coater at 78 nm, and heat-dried at 205 ° C. for 60 seconds to form an antireflection film. Thereafter, each positive resist composition immediately after preparation was applied by a spin coater and dried at 115 ° C. for 90 seconds (PB) to form a 200 nm resist film.
This resist film is exposed with an ArF excimer laser stepper (PAS5500 / 1100 NA = 0.75 (2/3 annular illumination) manufactured by ASML) through a mask, and immediately after exposure, heated on a hot plate at 120 ° C. for 90 seconds. (PEB). Further, the resist film was developed with an aqueous 2.38 mass% tetramethylammonium hydroxide solution at 23 ° C. for 60 seconds, rinsed with pure water for 30 seconds, and then dried to obtain a resist pattern.

(Resolution)
It was defined with a limiting resolution at an exposure amount for reproducing a 80 nm line and space 1/1 mask pattern.

(Line edge roughness)
The line edge edge roughness is measured by using a length-measuring scanning electron microscope (SEM) to observe a line-and-space 1/1 pattern of 80 nm, and the edge of the line pattern in the longitudinal direction should have an edge of 5 μm. The distance from the reference line was measured by 50 points using a length measurement SEM (Hitachi, Ltd. S-8840), the standard deviation was obtained, and 3σ was calculated. Smaller values indicate better performance

  From the results in Table 1, it is clear that the positive photosensitive composition of the present invention has excellent resolution and good line edge roughness.

Immersion exposure <Resist preparation>
The components of Examples 1 to 14 were dissolved in a solvent to prepare a solution having a solid concentration of 7% by mass, and this was filtered through a 0.1 μm polyethylene filter to prepare a positive resist composition. The prepared positive resist composition was evaluated by the following method.

<Resolution evaluation>
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied onto a silicon wafer and baked at 205 ° C. for 60 seconds to form a 78 nm antireflection film. The prepared positive resist composition was applied thereon and baked at 115 ° C. for 60 seconds to form a 150 nm resist film. The wafer thus obtained was subjected to two-beam interference exposure (wet exposure) using pure water as the immersion liquid. In the two-beam interference exposure (wet), a laser, an aperture, a shutter, three reflecting mirrors, and a condenser lens were used, and the wafer was exposed through a prism and an immersion liquid (pure water). The laser wavelength was 193 nm, and a prism that formed a 65 nm line and space pattern was used. Immediately after the exposure, the resist pattern obtained by heating at 115 ° C. for 90 seconds, developing with an aqueous tetramethylammonium hydroxide solution (2.38%) for 60 seconds, rinsing with pure water, and spin drying is then applied to a scanning electron microscope. When observed using Hitachi S-9260, a 65 nm line and space pattern was resolved.
It is clear that the positive photosensitive composition of the present invention has a good image forming ability even in an exposure method using an immersion liquid.

Claims (10)

(A) A repeating unit having a group represented by the following general formula (I) (excluding a repeating unit derived from a (meth) acrylate compound represented by the following general formula (MA) ), the following general formula (pA A resin having a repeating unit represented by formula (AI) and a repeating unit represented by the following general formula (AI), and having increased solubility in an alkali developer by the action of an acid; and
(B) A positive photosensitive composition containing a compound that generates an acid upon irradiation with an actinic ray or radiation (except for the following (A) and (I)).

In general formula (I),
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.

Here, R represents a hydrogen atom, a halogen atom, or a linear or branched alkyl group having 1 to 4 carbon atoms. A plurality of R may be the same or different.
A is a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, or a urea group, or a combination of two or more groups Represents.
Ra represents a group represented by any one of the following general formulas (pI) to (pVI).

In the formula, R ₁₁ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group or a sec-butyl group, and Z forms an alicyclic hydrocarbon group together with a carbon atom. Represents the atomic group necessary to do.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms, provided that at least one of R _{12 to} R ₁₄ , or Either R ₁₅ or R ₁₆ represents an alicyclic hydrocarbon group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{17 to} R ₂₁ Represents an alicyclic hydrocarbon group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or alicyclic hydrocarbon group having 1 to 4 carbon atoms.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or an alicyclic hydrocarbon group, provided that at least one of R _{22 to} R ₂₅ Represents an alicyclic hydrocarbon group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² and R ³ represent a hydrogen atom, or a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms, and R ² and R ³ are bonded to each other. In this case, R ² and R ³ represent a linear, branched or cyclic alkylene group having 2 to 15 carbon atoms. X is -CH ₂ -, - represents or -O-, or separated two -H groups together - CH ₂ CH _2. The dotted line is a norbornane ring, bicyclo [2.2.2] octane ring, 7-oxanorbornane ring, or a single bond that bonds the cyclohexane ring structure and the γ-butyrolactone ring structure, a divalent organic group, or between these two ring structures. Represents a structure sharing one or two constituent carbon atoms.
(A) (A) It contains a repeating unit having a partial structure represented by the following general formula (I ₀ ) and a repeating unit represented by the following general formula (II), and is soluble in an alkali developer by the action of an acid. A positive photoresist composition comprising: a resin having an increased number of ions; and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In the formula (I ₀ ), m1 represents an integer of 1 to 6. R ¹ and R ² each represents an alkyl group or a cyclic alkyl group, or R ¹ and R ² may be bonded to each other to form a cyclic alkyl group. R ³ and R ⁴ each represent a hydrogen atom, an alkyl group or a cyclic alkyl group, or R ³ and R ⁴ may be bonded to each other to form a cyclic alkyl group. R ^{5 to} R ⁷ each represents an alkyl group, a cyclic alkyl group, an aryl group, an allyl group, a trialkylsilyl group, or a trialkylsilyloxy group.

In formula (II), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L
¹ represents a single bond or a divalent linking group. X ¹ is —CO ₂ —, —O—, —CONH—, —CO
Represents a group selected from N (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OH, —OCH ₃ , —OCORa, —OCOORa, —OCONHRra, —O as substituents.
CON (Ra) (Rb), —NHCORa, —NHCOORa, —NHSO ₂ Ra, —N (R)
CORa, -N (R) COORa, -N (R) SO 2 Ra, -COOR, -CONHRa, -
It represents a saturated aliphatic group containing at least one functional group selected from the group consisting of CONHSO ₂ Ra, —CON (R) SO ₂ Ra, —CON (Ra) (Rb), and —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.
(A) (A) a repeating unit represented by at least one of the following general formulas (Ia) and (Ib) and a repeating unit represented by the following general formula (Ic), A positive photoresist composition containing a resin having increased solubility in a developer and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In formula (Ia), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L represents a single bond or a divalent linking group. R ^{1 to} R ⁴ each independently represents a hydrogen atom, SiR ′ (R ″) (R ′ ″), or an alkyl group that may contain SiR ′ (R ″) (R ′ ″) as a substituent. . However, not all of R ^{1 to} R ⁴ are hydrogen atoms. R ′, R ″, and R ′ ″ each independently represent a linear or branched alkyl group, phenyl group, trialkylsilyl group, or trialkylsilyloxy group.

In the formula (Ib), X ¹ represents an oxygen atom, a sulfur atom, or an alkylene group having 1 to 3 carbon atoms. L,
R ^{1 to} R ⁴ , R ′, R ″, and R ′ ″ are as defined above.

In formula (Ic), Y and L have the same meanings as in formula (Ia). X ² represents a group selected from —CO ₂ —, —O—, —CONH—, —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OCH ₃ , —OCORa, —OCOORa, —O as substituents.
CONHRa, -OCON (Ra) (Rb ), - NHCORa, -NHCOORa, -NHSO 2 Ra, -N (R) CORa, -N (R) COORa, -N (R) SO 2 Ra, -COOH, -
COOR, —CONHRa, —CONHSO ₂ Ra, —CON (R) SO ₂ Ra, —CON (
Ra) (Rb) represents a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.
A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
B ₂ is represented by any one of general formula (Lc) or general formulas (V-1) to (V-5).
Represents a group.

In general formula (Lc), Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , and Re ₁ are each independently a hydrogen atom or
Represents an alkyl group. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.
In the general formulas (V-1) to (V-5), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylsulfonylimino group, or an alkenyl group. Represents. Two of R _{1b to} R _5b may combine to form a ring. (A) A repeating unit having a group represented by the following general formula (I), a repeating unit represented by the following general formula (AII), and a repeating unit represented by the following general formula (AI), and the action of an acid A resin whose solubility in an alkaline developer increases, and
(B) A positive photosensitive composition containing a compound that generates an acid upon irradiation with an actinic ray or radiation (except for the following (A) and (I)).

In general formula (I),
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2.

In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group.
(A) (A) It contains a repeating unit having a partial structure represented by the following general formula (I ₀ ) and a repeating unit represented by the following general formula (II), and is soluble in an alkali developer by the action of an acid. A positive photoresist composition comprising: a resin having an increased number of ions; and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In the formula (I ₀ ), m1 represents an integer of 1 to 6. R ¹ and R ² each represents an alkyl group or a cyclic alkyl group, or R ¹ and R ² may be bonded to each other to form a cyclic alkyl group. R ³ and R ⁴ each represent a hydrogen atom, an alkyl group or a cyclic alkyl group, or R ³ and R ⁴ may be bonded to each other to form a cyclic alkyl group. R ^{5 to} R ⁷ each represents an alkyl group, a cyclic alkyl group, an aryl group, an allyl group, a trialkylsilyl group, or a trialkylsilyloxy group.

In formula (II), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L ¹ represents a single bond or a divalent linking group. X ¹ is —CO ₂ —, —O—, —CONH—, —CO
Represents a group selected from N (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OH, —OCH ₃ , —OCORa, —OCOORa, —OCONHRra, —O as substituents.
CON (Ra) (Rb), —NHCORa, —NHCOORa, —NHSO ₂ Ra, —N (R)
CORa, -N (R) COORa, -N (R) SO 2 Ra, -COOR, -CONHRa, -
It represents a saturated aliphatic group containing at least one functional group selected from the group consisting of CONHSO ₂ Ra, —CON (R) SO ₂ Ra, —CON (Ra) (Rb), and —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.
(A) (A) a repeating unit represented by at least one of the following general formulas (Ia) and (Ib) and a repeating unit represented by the following general formula (Ic), A positive photoresist composition containing a resin having increased solubility in a developer and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In formula (Ia), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L represents a single bond or a divalent linking group. R ^{1 to} R ⁴ each independently represents a hydrogen atom, SiR ′ (R ″) (R ′ ″), or an alkyl group that may contain SiR ′ (R ″) (R ′ ″) as a substituent. . However, not all of R ^{1 to} R ⁴ are hydrogen atoms. R ′, R ″, and R ′ ″ each independently represent a linear or branched alkyl group, phenyl group, trialkylsilyl group, or trialkylsilyloxy group.

In the formula (Ib), X ¹ represents an oxygen atom, a sulfur atom, or an alkylene group having 1 to 3 carbon atoms. L,
R ^{1 to} R ⁴ , R ′, R ″, and R ′ ″ are as defined above.

In formula (Ic), Y and L have the same meanings as in formula (Ia). X ² represents a group selected from —CO ₂ —, —O—, —CONH—, —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OCH ₃ , —OCORa, —OCOORa, —O as substituents.
CONHRa, -OCON (Ra) (Rb ), - NHCORa, -NHCOORa, -NHSO 2 Ra, -N (R) CORa, -N (R) COORa, -N (R) SO 2 Ra, -COOH, -COOR _{, -CONHRa, -CONHSO 2 Ra, -CON} (R) SO 2 Ra, -CON (
Ra) (Rb) represents a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.
A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
B ₂ is represented by any one of general formula (Lc) or general formulas (V-1) to (V-5).
Represents a group.

In general formula (Lc), Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , and Re ₁ are each independently a hydrogen atom or
Represents an alkyl group. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.
In the general formulas (V-1) to (V-5), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylsulfonylimino group, or an alkenyl group. Represents. Two of R _{1b to} R _5b may combine to form a ring. The positive photosensitive composition according to claim 1 or 2, wherein the repeating unit having a group represented by the general formula (I) is represented by the following general formula (I ').

In general formula (I ′),
Ra ₁ represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
L ₁ represents a monocyclic or polycyclic (m + 1) -valent alicyclic hydrocarbon group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
m represents an integer of 1 or 2. In general formula (I) or general formula (I ′), L ₁ is a monocyclic or polycyclic (m + 1) valent group selected from cyclopentane, cyclohexane, norbornane, adamantane, tricyclodecane and tetracyclododecane. The positive photosensitive composition according to claim 1, wherein the positive photosensitive composition is an alicyclic hydrocarbon group. (A) It has a repeating unit represented by any one of the following general formulas (1) to (3) and a repeating unit represented by the following general formula (AII), and the solubility in an alkali developer is increased by the action of an acid. Resin and
(B) A positive photosensitive composition containing a compound that generates an acid upon irradiation with an actinic ray or radiation (excluding the following (A) and (I)):
.

Ra ₁ represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure.
Rb ₁ represents a substituent, and when a plurality of Rb ₁ are present, they may be the same or different.
n ₁ represents an integer of 0 to 3.

In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group.
(A) (A) It contains a repeating unit having a partial structure represented by the following general formula (I ₀ ) and a repeating unit represented by the following general formula (II), and is soluble in an alkali developer by the action of an acid. A positive photoresist composition comprising: a resin having an increased number of ions; and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In the formula (I ₀ ), m1 represents an integer of 1 to 6. R ¹ and R ² each represents an alkyl group or a cyclic alkyl group, or R ¹ and R ² may be bonded to each other to form a cyclic alkyl group. R ³ and R ⁴ each represent a hydrogen atom, an alkyl group or a cyclic alkyl group, or R ³ and R ⁴ may be bonded to each other to form a cyclic alkyl group. R ^{5 to} R ⁷ each represents an alkyl group, a cyclic alkyl group, an aryl group, an allyl group, a trialkylsilyl group, or a trialkylsilyloxy group.

In formula (II), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L ¹ represents a single bond or a divalent linking group. X ¹ is —CO ₂ —, —O—, —CONH—, —CO
Represents a group selected from N (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OH, —OCH ₃ , —OCORa, —OCOORa, —OCONHRra, —O as substituents.
CON (Ra) (Rb), —NHCORa, —NHCOORa, —NHSO ₂ Ra, —N (R)
CORa, -N (R) COORa, -N (R) SO 2 Ra, -COOR, -CONHRa, -
It represents a saturated aliphatic group containing at least one functional group selected from the group consisting of CONHSO ₂ Ra, —CON (R) SO ₂ Ra, —CON (Ra) (Rb), and —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.
(A) (A) a repeating unit represented by at least one of the following general formulas (Ia) and (Ib) and a repeating unit represented by the following general formula (Ic), A positive photoresist composition containing a resin having increased solubility in a developer and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In formula (Ia), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L represents a single bond or a divalent linking group. R ^{1 to} R ⁴ each independently represents a hydrogen atom, SiR ′ (R ″) (R ′ ″), or an alkyl group that may contain SiR ′ (R ″) (R ′ ″) as a substituent. . However, not all of R ^{1 to} R ⁴ are hydrogen atoms. R ′, R ″, and R ′ ″ each independently represent a linear or branched alkyl group, phenyl group, trialkylsilyl group, or trialkylsilyloxy group.

In the formula (Ib), X ¹ represents an oxygen atom, a sulfur atom, or an alkylene group having 1 to 3 carbon atoms. L,
R ^{1 to} R ⁴ , R ′, R ″, and R ′ ″ are as defined above.

In formula (Ic), Y and L have the same meanings as in formula (Ia). X ² represents a group selected from —CO ₂ —, —O—, —CONH—, —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OCH ₃ , —OCORa, —OCOORa, —O as substituents.
CONHRa, -OCON (Ra) (Rb ), - NHCORa, -NHCOORa, -NHSO 2 Ra, -N (R) CORa, -N (R) COORa, -N (R) SO 2 Ra, -COOH, -COOR _{, -CONHRa, -CONHSO 2 Ra, -CON} (R) SO 2 Ra, -CON (
Ra) (Rb) represents a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted. (A) a resin having a repeating unit represented by the following general formula (4) and a repeating unit represented by the following general formula (AII), which increases the solubility in an alkali developer by the action of an acid; and
(B) A positive photosensitive composition containing a compound that generates an acid upon irradiation with an actinic ray or radiation (except for the following (A) and (I)).

Ra ₁ represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.
Rb ₁ represents a substituent, and when a plurality of Rb ₁ are present, they may be the same or different.
n ₁ represents an integer of 0 to 3.
X ₁ represents a single bond or a divalent linking group.
Lc ₁ represents a group having a lactone structure represented by the following general formula (LC1-1) or (LC1-2).

n ₂ represents an integer of 0 to 3.
Rb ₂ represents a substituent.

In general formula (AII), R ₁ c represents a hydrogen atom or a methyl group.
R ₂ c to R ₄ c each independently represents a hydrogen atom or a hydroxyl group. However, at least one of R ₂ c to R ₄ c represents a hydroxyl group.
(A) (A) It contains a repeating unit having a partial structure represented by the following general formula (I ₀ ) and a repeating unit represented by the following general formula (II), and is soluble in an alkali developer by the action of an acid. A positive photoresist composition comprising: a resin having an increased number of ions; and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In the formula (I ₀ ), m1 represents an integer of 1 to 6. R ¹ and R ² each represents an alkyl group or a cyclic alkyl group, or R ¹ and R ² may be bonded to each other to form a cyclic alkyl group. R ³ and R ⁴ each represent a hydrogen atom, an alkyl group or a cyclic alkyl group, or R ³ and R ⁴ may be bonded to each other to form a cyclic alkyl group. R ^{5 to} R ⁷ each represents an alkyl group, a cyclic alkyl group, an aryl group, an allyl group, a trialkylsilyl group, or a trialkylsilyloxy group.

In formula (II), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L ¹ represents a single bond or a divalent linking group. X ¹ represents a group selected from —CO ₂ —, —O—, —CONH—, and —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A represents a group containing a lactone structure, a group containing a lactam structure, and —OH, —OCH ₃ , —OCORa, —OCOORa, —OCONHRa, —OCON (Ra) (Rb), —NHCORa, —NHCOORa, —NHSO as substituents ₂ Ra, -N (R) CORa, -N (R) COORa, -N (R) SO ₂ Ra, -COOR, -CONHRa, -CONHSO ₂ Ra, -CON (R) SO ₂ Ra, -CON (Ra ) (Rb), a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted.
(A) (A) a repeating unit represented by at least one of the following general formulas (Ia) and (Ib) and a repeating unit represented by the following general formula (Ic), A positive photoresist composition containing a resin having increased solubility in a developer and (B) a compound that generates an acid upon irradiation with actinic rays or radiation.

In formula (Ia), Y represents a group selected from a hydrogen atom, a methyl group, a cyano group, and a chlorine atom. L represents a single bond or a divalent linking group. R ^{1 to} R ⁴ each independently represents a hydrogen atom, SiR ′ (R ″) (R ′ ″), or an alkyl group that may contain SiR ′ (R ″) (R ′ ″) as a substituent. . However, not all of R ^{1 to} R ⁴ are hydrogen atoms. R ′, R ″, and R ′ ″ each independently represent a linear or branched alkyl group, phenyl group, trialkylsilyl group, or trialkylsilyloxy group.

In the formula (Ib), X ¹ represents an oxygen atom, a sulfur atom, or an alkylene group having 1 to 3 carbon atoms. L, R ^{1 to} R ⁴ , R ′, R ″, and R ′ ″ are as defined above.

In formula (Ic), Y and L have the same meanings as in formula (Ia). X ² represents a group selected from —CO ₂ —, —O—, —CONH—, and —CON (R) —. Here, R represents an optionally substituted alkyl or aryl group having 1 to 10 carbon atoms. A is a group containing a lactone structure, a group containing a lactam structure, -OCH _3, -OCORa as a substituent, -OCOORa, -OCONHRa, -OCON (Ra ) (Rb), - NHCORa, -NHCOORa, -NHSO 2 Ra, -N (R) CORa, -N ( R) COORa, -N (R) SO 2 Ra, -COOH, -COOR, -CONHRa, -CONHSO 2 Ra, -CON (R) SO 2 Ra, -CON (Ra ) (Rb), a saturated aliphatic group containing at least one functional group selected from the group of —CN. Here, R, Ra, and Rb each independently represent an alkyl or aryl group having 1 to 10 carbon atoms that may be substituted. Furthermore, the positive photosensitive composition of Claim 5 or 6 containing the repeating unit represented by the following general formula (AI).

In general formula (AI), R _b0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.
A ′ represents a single bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group obtained by combining these.
B ₂ represents a group represented by any one of general formula (Lc) and general formulas (V-1) to (V-5).

In general formula (Lc), Ra ₁ , Rb ₁ , Rc ₁ , Rd ₁ , and Re ₁ each independently represent a hydrogen atom or an alkyl group. m and n each independently represents an integer of 0 to 3, and m + n is 2 or more and 6 or less.
In the general formulas (V-1) to (V-5), R _{1b to} R _5b each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylsulfonylimino group, or an alkenyl group. Represents. Two of R _{1b to} R _5b may combine to form a ring. The positive electrode according to any one of claims 1 to 7 , further comprising (D) a dissolution inhibiting compound having a molecular weight of 3000 or less, which decomposes by the action of an acid and increases the solubility in an alkaline developer. Type photosensitive composition. A pattern forming method comprising a step of forming a film with the positive photosensitive composition according to claim 1 , and exposing and developing the film. The pattern forming method according to claim 9 , wherein exposure is performed through an immersion liquid.