diff --git a/qiskit_classroom/converter_presenter.py b/qiskit_classroom/converter_presenter.py
index 7767d3c..5e4256d 100644
--- a/qiskit_classroom/converter_presenter.py
+++ b/qiskit_classroom/converter_presenter.py
@@ -136,8 +136,8 @@ async def on_convert_button_clicked(self) -> None:
             result = await self.model.convert_and_draw(
                 shows_result=self.view.get_shows_result()
             )
-        except RuntimeError:
-            self.view.show_alert_message("conversion processe error")
+        except RuntimeError as exc:
+            self.view.show_alert_message("conversion processe error\n" + exc.__str__())
         except TimeoutExpired:
             self.view.show_alert_message("conversion process timeout error")
         except FileNotFoundError:
diff --git a/qiskit_classroom/worker.py b/qiskit_classroom/worker.py
index 37c9070..5cb71ca 100644
--- a/qiskit_classroom/worker.py
+++ b/qiskit_classroom/worker.py
@@ -54,6 +54,7 @@ def add_new_line(strings: list[str]) -> str:
 class ConverterWorker:
     """worker for convert expression and visualize expression"""
 
+    # pylint: disable=too-many-arguments
     def __init__(
         self,
         from_expression: QuantumExpression,
@@ -79,7 +80,11 @@ def generate_random_file_name() -> str:  # pragma: no cover
         Returns:
             str: generated file name
         """
-        return "".join(random.choice(string.ascii_letters) for _ in range(10)) + ".py"
+        return (
+            "/tmp/"
+            + "".join(random.choice(string.ascii_letters) for _ in range(10))
+            + ".py"
+        )
 
     @staticmethod
     def write_converting_code(file_path: str, code: str) -> bool:  # pragma: no cover
@@ -170,9 +175,13 @@ def generate_visualization_code(self) -> str:
             if self.to_expression is QuantumExpression.MATRIX:
                 return add_new_line(
                     [
-                        "for gate, name in zip(reversed(result['gate']), reversed(result['name'])):",
-                        """\tprint(f'{gate.strip()}_' + '{' + "\\\\otimes ".join(name[1]) + '}')""",
-                        "print(f\"={result['result']}_{{result}}\")"
+                        (
+                            "for gate, name in zip(reversed(result['gate']),"
+                            + "reversed(result['name'])):"
+                        ),
+                        "\totimes=' \\\\otimes '",
+                        """\tprint('\\stackrel{' + otimes.join(name[1]) +'}' + f'{{{gate}}}')""",
+                        "print(f\"= \\stackrel{{result}}{{{result['result']}}}\")"
                         if self.shows_result
                         else "",
                     ]
diff --git a/requirements.txt b/requirements.txt
index 939d4d4..5294a22 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,6 @@
 qiskit==0.44.1
 PySide6==6.5.1.1
 qasync==0.24.0
-qiskit-classroom-converter==0.3.0
+qiskit-classroom-converter==0.4.0
 matplotlib==3.7.2
 pylatexenc==2.10
\ No newline at end of file
diff --git a/tests/test_worker.py b/tests/test_worker.py
index 3e4e3d4..878adf3 100644
--- a/tests/test_worker.py
+++ b/tests/test_worker.py
@@ -42,8 +42,9 @@
     "converter = ConversionService(conversion_type='QC_TO_MATRIX',"
     + " option={'print': 'raw'})\n"
     + f"result = converter.convert(input_value={VALUE_NAME})",
-    "for gate, name in zip(reversed(result['gate']), reversed(result['name'])):\n"
-    + "\tprint(f'{gate.strip()}_' + '{' + \"\\\\otimes \".join(name[1]) + '}')\n",
+    "for gate, name in zip(reversed(result['gate']),reversed(result['name'])):\n"
+    + "\totimes=' \\\\otimes '\n"
+    + "\tprint('\\stackrel{' + otimes.join(name[1]) +'}' + f'{{{gate}}}')\n",
 ]
 
 MATRIX_TO_QC_EXPECTED = [