Abstract: A number of air actuated valves are added to a conventional apparatus for treating semiconductor wafers with HMDS, hexamethyl-disilazane, vapor to improve the adhesion between the wafers and resist layers. These valves allow for automatic purging of the HMDS vapor from the pipes in the apparatus by dry nitrogen thereby preventing HMDS vapor condensation in the pipes which leads to contamination of the HMDS supply. The valve system prevents any backstreaming of nitrogen gas into the HMDS supply tank.

Abstract: A circuit for use with optical inspection lamps, e.g., tungsten-halogen or Marco lamps, in semiconductor fabrication machines performing ADI and AEI operations, that will lower the operating voltage of the lamps when the machine is not being used by an operator, while providing full light intensity during optical inspections. The circuit is coupled into the Marco lamp power supply and contains two micro-switches, each containing two sets of switch contacts normally configured with one set closed and one set open to render one micro-switch closed providing the operating voltage to the lamp and the other open rendering the circuit inactive in this condition. The micro-switches have operating levers that cooperate with indexes which follow the position of cassette elevators that deliver the semiconductor wafers for processing and each of which has an "up" and a "down" position.

Abstract: A method and apparatus for cleaning a spray stream nozzle employed in dispensing upon a photoexposed blanket photoresist layer formed over a semiconductor substrate a photoresist developer solution. There is first provided a spray stream nozzle having a minimum of one aperture formed therein. There is then provided through the spray stream nozzle a volume of a photoresist developer solution sufficient to develop a photoexposed blanket photoresist layer formed over a semiconductor substrate placed beneath the spray stream nozzle. Finally, there is provided then through the spray stream nozzle a volume of a solvent which is not susceptible to clogging the spray stream nozzle.

Abstract: A number of air actuated valves are added to a conventional apparatus for treating semiconductor wafers with HMDS, hexamethyl-disilazane, vapor to improve the adhesion between the wafers and resist layers. These valves allow for automatic purging of the HMDS vapor from the pipes in the apparatus by dry nitrogen thereby preventing HMDS vapor condensation in the pipes which leads to contamination of the HMDS supply. The valve system prevents any backstreaming of nitrogen gas into the HMDS supply tank.

Abstract: A heat treatment control system to cure a photoresist that is deposited upon a semiconductor substrate is described. The heat treatment system has a hot plate with a heating element and temperature sensing devices that are in close proximity to the semiconductor substrate. The heat treatment system also has a controlling device that will selectively provide an electrical power source to the heating element to heat the semiconductor wafer. The coupling of the heating element to an electrical power source is determined by an electrical signal from one of the temperature sensing devices that have been conditioned and compared to a set temperature signal to provide an error signal. The controlling device will examine the error signal and adjust the temperature. An over temperature alarm circuit is connected to the second temperature sensing device.