diff --git a/gf180mcu/magic/gf180mcu.tech b/gf180mcu/magic/gf180mcu.tech
index aff87bb..0b34391 100644
--- a/gf180mcu/magic/gf180mcu.tech
+++ b/gf180mcu/magic/gf180mcu.tech
@@ -675,6 +675,12 @@
 	calma	12 0
 
 #-----------------------------------------------------
+# SUBCUT
+#-----------------------------------------------------
+ layer SUBCUT	isosub
+	calma	23 5
+
+#-----------------------------------------------------
 # NWELL
 #-----------------------------------------------------
  layer NWELL 	allnwell
@@ -1595,6 +1601,9 @@
  layer dnwell DNWELL
  labels DNWELL
 
+ layer isosub SUBCUT
+ labels SUBCUT
+
  templayer ndiffarea DIFF
  and-not POLY
  and-not NWELL
@@ -2622,6 +2631,7 @@
  calma NWELLTXT 21 10
  calma PWELL 204 0
  calma PWELLTXT 204 10
+ calma SUBCUT 23 5
  calma DIFF 22 0
  calma DIFFFILL 22 4
  calma POLY 30 0
@@ -3582,7 +3592,7 @@
 # See document 180MCU_YI-141-EP059-01_10.pdf
 
  resist (nwell,dnwell)/well      1000000
- resist (pwell)/well	 	 3250000
+ resist (pwell,isosub)/well 	 3250000
 
  resist (*ndiff,nsd)/active 	  6300
  resist (*pdiff,*psd)/active	  7000
@@ -3686,7 +3696,7 @@
  # High-end corner resistances (milliohms per square)
 
  resist (nwell,dnwell)/well      1200000
- resist (pwell)/well	 	 3250000
+ resist (pwell,isosub)/well 	 3250000
 
  resist (*ndiff,nsd)/active 	 15000
  resist (*pdiff,*psd)/active	 15000
@@ -3790,7 +3800,7 @@
  # Low-end corner resistances (milliohms per square)
 
  resist (nwell,dnwell)/well       800000
- resist (pwell)/well	 	 3250000
+ resist (pwell,isosub)/well 	 3250000
 
  resist (*ndiff,nsd)/active 	  1000
  resist (*pdiff,*psd)/active	  1000