Abstract: A method and system for testing one or more semiconductor structures, for example, chips or wafers, in a three-dimensional stack. The method and system includes controlling a logic signal of a first circuit in a first chip or wafer connected to a supply voltage to indicate a first state during pre-assembly testing of the first chip or wafer. The method and system further includes controlling the logic signal to indicate a second state when the first circuit is connected to a second circuit of a second chip or wafer resulting in a combined circuit. The combined circuit is in a three-dimensional chip or wafer stack during post-assembly testing of the three-dimensional chip or wafer stack.

Abstract: A method and system for testing one or more semiconductor structures, for example, chips or wafers, in a three-dimensional stack. The method and system includes controlling a logic signal of a first circuit in a first chip or wafer connected to a supply voltage to indicate a first state during pre-assembly testing of the first chip or wafer. The method and system further includes controlling the logic signal to indicate a second state when the first circuit is connected to a second circuit of a second chip or wafer resulting in a combined circuit. The combined circuit is in a three-dimensional chip or wafer stack during post-assembly testing of the three-dimensional chip or wafer stack.

Abstract: A random intrinsic chip ID generation employs a retention fail signature. A 1st and 2nd ID are generated using testing settings with a 1st setting more restrictive than the 2nd, creating more fails in the 1st ID bit string that includes 2nd ID bit string. A retention pause time controls the number of retention fails, adjusted by a BIST engine, wherein the fail numbers satisfy a predetermined fail target. Verification confirms whether the 1st ID includes the 2nd ID bit string, the ID being the one used for authentication. Authentication is enabled by a 3rd ID with intermediate condition such that 1st ID includes 3rd ID bit string and 3rd ID includes 2nd ID bit string. The intermediate condition includes a guard-band to eliminate bit instability problem near the 1st and 2nd ID boundary. The intermediate condition is changed at each ID read operation, resulting in a more secure identification.

Abstract: A random intrinsic chip ID generation employs a retention fail signature. A 1st and 2nd ID are generated using testing settings with a 1st setting more restrictive than the 2nd, creating more fails in the 1st ID bit string that includes 2nd ID bit string. A retention pause time controls the number of retention fails, adjusted by a BIST engine, wherein the fail numbers satisfy a predetermined fail target. Verification confirms whether the 1st ID includes the 2nd ID bit string, the ID being the one used for authentication. Authentication is enabled by a 3rd ID with intermediate condition such that 1st ID includes 3rd ID bit string and 3rd ID includes 2nd ID bit string. The intermediate condition includes a guard-band to eliminate bit instability problem near the 1st and 2nd ID boundary. The intermediate condition is changed at each ID read operation, resulting in a more secure identification.