diff --git a/technology/freepdk45/tech/tech.py b/technology/freepdk45/tech/tech.py
index a76624d4..79773878 100644
--- a/technology/freepdk45/tech/tech.py
+++ b/technology/freepdk45/tech/tech.py
@@ -12,6 +12,11 @@ from module_type import *
 """
 File containing the process technology parameters for FreePDK 45nm.
 """
+
+###################################################
+# Custom modules
+###################################################
+
 # This uses the default classes to instantiate module from
 # '$OPENRAM_HOME/compiler/modules'.
 # Using tech_modules['cellname'] you can override each class by providing a custom
@@ -19,7 +24,11 @@ File containing the process technology parameters for FreePDK 45nm.
 # For example: tech_modules['contact'] = 'contact_freepdk45'
 tech_modules = ModuleType()
 
-#GDS file info
+
+###################################################
+# GDS file info
+###################################################
+
 GDS = {}
 # gds units 
 # From http://www.cnf.cornell.edu/cnf_spie9.html: "The first
diff --git a/technology/scn4m_subm/tech/tech.py b/technology/scn4m_subm/tech/tech.py
index beb604c5..3fb7acc0 100644
--- a/technology/scn4m_subm/tech/tech.py
+++ b/technology/scn4m_subm/tech/tech.py
@@ -12,6 +12,11 @@ from module_type import *
 """
 File containing the process technology parameters for SCMOS 4m, 0.35um
 """
+
+###################################################
+# Custom modules
+###################################################
+
 # This uses the default classes to instantiate module from
 # '$OPENRAM_HOME/compiler/modules'.
 # Using tech_modules['cellname'] you can override each class by providing a custom
@@ -19,7 +24,10 @@ File containing the process technology parameters for SCMOS 4m, 0.35um
 # For example: tech_modules['contact'] = 'contact_scn4m'
 tech_modules = ModuleType()
 
-#GDS file info
+
+###################################################
+# GDS file info
+###################################################
 GDS={}
 # gds units
 # From http://www.cnf.cornell.edu/cnf_spie9.html: "The first
@@ -69,8 +77,6 @@ preferred_directions = {"poly": "V",
 
 # create the GDS layer map
 layer={} 
-layer["vtg"]            = None
-layer["vth"]            = None
 layer["pwell"]          = (41, 0)
 layer["nwell"]          = (42, 0)
 layer["active"]         = (43, 0)