On the surface of a semiconductor wafer there is formed a binary-coded pattern which has high and low reflection portions and which contains an item of wafer processing information. A scanning device is provided to scan such patterns on individual wafers in order to obtain items of scanned information. Further a control device is provided to store the items of wafer processing information. Upon receipt of an item of scanning information, the control device produces a control signal which corresponds to the item of scanning information. The control signal is supplied to one of wafer processors, which effects on the semiconductor wafer the process necessary to manufacture a semiconductor device.

A semiconductor fabrication apparatus including a plurality of process units for sequentially processing a semiconductor wafer. A heating unit, a cooling unit, a resin coating unit, and a resin hardening unit are included. Also, a sender unit and a process control unit are included besides the process units. In the sender unit, a wafer size sensor is provided in order to detect the size of an original wafer. The wafer size data detected by the sensor is held and processed in the process control unit. Finding the original size of a wafer, the process control unit gives instructions to process units so as to set a correct stop position of the wafer and to select suitable wafer supporting means according to the detected wafer size. Thus, the apparatus is automatically set to a correct state for uniformly processing the semiconductor wafer. In some units, there are provided sensors to find the size of the supporting means, for example, carrier guides, forks, and stoppers. When the information from these sensors do not correspond to the wafer size detected by the wafer size sensor, the process control unit interrupts fabrication processes under execution and gives an alarm to operators.

A statistical method of monitoring the yield of a gate oxide layer. A voltage is applied to first test keys and second test keys to build curves showing relationship between failure distribution and charge density, wherein each of the first test keys has a first oxide area and each of the second test keys has a second oxide area. A yield of the first test keys and a yield of the second test keys up to a charge density can be obtained. The yields of the first test keys and the second test keys have a relationship as an equation of area. To obtain a yield of small test keys, a yield and area of large test keys are imported into an equation. According to operating the equation, the yield of a small gate oxide is obtained.

To automatic assembly of a semiconductor device, a robot having 6 degrees of freedom is provided for effecting conveyance among prior automated devices. The robot includes a readout means for reading an identification number of a magazine for housing lead frames therein for identifying each magazine. The robot also includes a sampling station for quality control within the working range thereof. The robot includes a control means for storing magazines drawn out for quality control. Accordingly, no disturbance is produced in article flows among the component devices. The system further includes an inputting means for inputting a lot number of lead frames within the magazines. Thus, lots are reliably controlled because of one-to-one correspondence between the lot number and the identification number of the magazine.

A method for selectively altering a thickness of a radiation sensitive polymer layer including providing a substrate including at least one radiation sensitive polymer layer having a first thickness topography; exposing the at least one radiation sensitive polymer layer through a mask having a predetermined radiant energy transmittance distribution to selectively expose predetermined areas of the at least one sensitive polymer layer to predetermined radiant energy dosages; and, developing the at least one radiation sensitive polymer layer to alter the first thickness topography of the at least one radiation sensitive polymer layer to produce a second thickness topography.