Hitachi-high-technologies Corporation

Hitachi High-tech Corporation

Takumi Tandou

Masaru Izawa

Kenetsu Yokogawa

Ken'etsu Yokogawa

Seiichiro Kanno

Go Miya

Hiroshi Ito

Tomoyuki Watanabe

Naoki Yasui

Tsutomu Tetsuka

Akitaka Makino

Yutaka Kouzuma

Takamasa Ichino

Hiromichi Kawasaki

Tetsuo Kawanabe

Provided is a plasma processing apparatus including: a processing chamber; a sample stage placed inside the processing chamber; a processing gas supply unit which supplies processing gas into the processing chamber; a high-frequency power supply which supplies an electric field inside the processing chamber; an electrostatic chuck unit disposed on the sample stage in which openings to flow heat transfer gas are formed; a refrigerant supply unit which supplies a refrigerant inside the sample stage; and a control unit, wherein the control unit controls a heat transfer gas supply unit to control the temperature of a wafer depending on a plurality of processes for processing the wafer by switching a flow rate of the heat transfer gas or the type of the heat transfer gas flowing out of the openings between a concave portion formed in the electrostatic chuck unit and the wafer attracted to the electrostatic chuck unit.

Wafer processing method and wafer processing apparatus

A plasma processing apparatus including: a processing chamber; a sample stage; a vacuum exhaust unit; and a plasma generation unit, the sample stage includes: a first metallic base material having a refrigerant flow path formed therein; a second metallic base material disposed above the first metallic base material and has a lower thermal conductivity than the first metallic base material; and a plurality of lift pins vertically moving the object to be processed with respect to the sample stage. A plurality of through-holes through which the plurality of the lift pins passes is formed in the first and the second metallic base material, and a boss, which electrically insulates the lift pin from the first and the second metallic base material and is formed using an insulating member having a higher thermal conductivity than the second metallic base material, is inserted into each of the plurality of through-holes.

Plasma processing apparatus

A plasma processor, including a first gas supplier to supply first gas to the inside of a vacuum vessel, a stage on which a wafer is placed, an electromagnetic wave supplier to supply electromagnetic waves for generating first plasma, a susceptor provided to an outer peripheral portion of the stage, a second high frequency power source connected to the susceptor, and a second gas supplier to supply second gas to the inside of the susceptor. The inside of the susceptor is provided with a high frequency electrode connected to the second high frequency power source and a first earth electrode disposed opposite to the high frequency electrode. The second high frequency power source supplies high frequency power while the second gas supplier supplies the second gas, thereby generating second plasma inside the susceptor.

A plasma processing apparatus includes: a refrigerating cycle including a refrigerant passage, a compressor, and a condenser, all of which are coupled in this order, and through which a refrigerant flows in this order, the refrigerant passage being disposed inside a sample stage and through which the refrigerant flows to serve as an evaporator; first and second expansion valves which are interposed between the condenser and the refrigerant passage and between the refrigerant passage and the compressor respectively in the refrigerating cycle; a vaporizer that is interposed between the second expansion valve and the compressor in the refrigerating cycle and which heats and vaporizes the refrigerant; and a controller which regulates opening and closing of the first and second expansion valves and regulates a refrigerant heat exchange amount of the condenser or vaporizer based on a refrigerant temperature between the condenser and the second expansion valve.

Plasma processing apparatus and plasma processing method

A sample stage includes plural pushup pins that move a sample up/down above the stage, a recessed and protruding dielectric film on which the sample is loaded, a feeding port disposed on the film and through which gas is fed to a gap between the sample and the film, and openings of through-holes in which the pushup pins are housed, and the stage is connected to a feeding and evacuation conduit including a feeding path that communicates with the port and through which gas fed to the gap flows, an evacuation path that communicates with the opening and through which gas fed to the gap is discharged, and a connection path through which the feeding path and the evacuation path communicate. With communication between the feeding path and the evacuation path via the connection path interrupted, gas from the feeding path is fed to the gap and into the through-hole via the gap.

Plasma processing apparatus with gas feed and evacuation conduit

A plasma processing method is provided for a plasma processing apparatus which includes a plurality of upstream-side expansion valves and a plurality of downstream-side expansion valves connected to respective refrigerant inlets and respective refrigerant outlets to adjust a flow rate or a pressure of a refrigerant flowing into the respective refrigerant inlets and a flow rate or a pressure of a refrigerant flowing out from the respective refrigerant outlets. The method includes adjusting openings of the upstream-side expansion valves and openings of the downstream-side expansion valves so that no change in flow rate of the refrigerant occurs in a plurality of refrigerant channels between the plurality of upstream-side expansion valves and the plurality of downstream-side expansion valves via the plurality of refrigerant channels in a refrigeration cycle allowing the refrigerant to flow therein.

The present invention provides a temperature control unit for an electrostatic adsorption electrode that is capable of controlling the wafer temperature rapidly over a wide temperature range without affecting in-plane uniformity while high heat input etching is conducted with high wafer bias power applied. A refrigerant flow path provided in the electrostatic adsorption electrode serves as an evaporator. The refrigerant flow path is connected to a compressor, a condenser, and a first expansion valve to form a direct expansion type refrigeration cycle. A second expansion valve is installed between the electrostatic adsorption electrode and the compressor to adjust the flow rate of a refrigerant. This makes it possible to compress the refrigerant in the refrigerant flow path of the electrostatic adsorption electrode and adjust the wafer temperature to a high level by raising the refrigerant evaporation temperature. Further, a thin-walled cylindrical refrigerant flow path is employed so that the thin-walled cylinder is deformed only slightly by the refrigerant pressure.

A plasma processing apparatus includes a processing chamber, a wafer table, a refrigerant passage disposed inside the wafer table in which a refrigerant flows, a refrigeration cycle comprising the refrigerant passage in the wafer table as a first evaporator in which the refrigerant is evaporated as a result of a heat-exchange therein, a compressor, a condenser and an expansion valve, a second evaporator, and a controlling unit which adjusts a number of rotations of the compressor based upon a degree of dryness of the refrigerant at a position on the refrigeration cycle after passing through the first evaporation in a range in which dry-out does not occur in the first evaporator, and the dryness of the refrigerant being determined based upon an amount of a heat exchange during the evaporation of the refrigerant in the second evaporator.

Vacuum processing apparatus and plasma processing apparatus with temperature control function for wafer stage

There is provided a means for uniformly controlling the in-plane temperature of a semiconductor wafer at high speed in a high heat input etching process. A refrigerant channel structure in a circular shape is formed in a sample stage. Due to a fact that a heat transfer coefficient of a refrigerant is largely changed from a refrigerant supply port to a refrigerant outlet port, the cross sections of the channel structure is structured so as to be increased from a first channel areas towards a second channel areas in order to make the heat transfer coefficient of the refrigerant constant in the refrigerant channel structure. Thereby, the heat transfer coefficient of the refrigerant is prevented from increasing by reducing the flow rate of the refrigerant at a dry degree area where the heat transfer coefficient of the refrigerant is increased. Further, the cross section of the channel structure is structured so as to be reduced from the second channel areas towards a third channel areas, and thereby the heat transfer coefficient of the refrigerant is prevented from decreasing. Accordingly, the heat transfer coefficient of the refrigerant can be uniformed in the channel structure.

In a plasma processing apparatus, a check valve is installed close to a refrigerant inlet of a compressor. When performing maintenance of a sample stage, refrigerant collected from a refrigerant flow path is temporarily stored in a flow path section extending from an expansion valve to the check valve, making it possible to perform the maintenance without changing the amount of refrigerant in the refrigerating cycle. With a refrigerant storage tank, a refrigerant supply valve, and a refrigerant discharge valve included in the refrigerating cycle, when maintenance of the compressor, a condenser, or the expansion valve is performed, the refrigerant collected from the refrigerating cycle can be put in use again.

Plasma processing apparatus and maintenance method therefor

The present invention provides means for controlling the temperature of a semiconductor wafer rapidly and uniformly in plane during etching processing by a large quantity of input heat by use of a refrigerating system by the heat of evaporation. A ring-shaped refrigerant passage is formed in a sample stand. Since the heat transfer rate and pressure loss of a refrigerant increase from a refrigerant supply port to a refrigerant ejection port as dryness degrees increase, these must be restricted. Therefore, constructionally, a supply refrigerant quantity is controlled to prevent the refrigerant from completely evaporating within the refrigerant passage, and the sectional areas of the refrigerant passage increase successively from a first passage to a third passage.

A wafer stage includes a first evaporator where a refrigerant circulates. The first evaporator makes up a cooling cycle with a compressor, first condenser, expansion valve, second evaporator, refrigerant thermometer, and refrigerant flowmeter. The first condenser is supplied with a heat exchange medium. The temperature of a coolant supplied to the second evaporator is measured by an inlet refrigerant thermometer and outlet refrigerant thermometer, while the flow rate of the coolant is monitored and adjusted by a flow-rate adjuster. The temperature difference in the coolant between being at the inlet and at the outlet and flow rate can be measured. Upon complete evaporation of the refrigerant in the second evaporator, the dryness of the refrigerant discharged from the wafer stage is calculated from the amount of heat absorbed from (exchanged with) the coolant, the circulation amount of the refrigerant and the refrigerant temperature to control the rotational speed of the compressor.

A plasma processing apparatus includes a processing chamber encased in a vacuum vessel equipped with an evacuator; a sample stage located in the processing chamber and having an upper surface on which a sample as an object to be processed rests; a gas feeding unit for feeding processing gas into the processing chamber; a plurality of refrigerant ducts which are laid out in the internal of the sample stage and through which liquid refrigerant flows and can be evaporated; a cooling circuit including a compressor, a condenser, an expansion valve and a set of pipelines to connect the compressor, the condenser and the expansion valve in this order; and a selecting unit for selectively feeding the refrigerant through the plural refrigerant ducts in the different steps of the processing. The sample is processed by using plasma while the temperature of the sample stage is being controlled by the cooling circuit.

A plasma processing apparatus is provided which processes a sample held on a sample table arranged in a process chamber in a vacuum container by using a plasma formed in the process chamber. The plasma processing apparatus comprises: paths arranged in the sample table in which a coolant is supplied and vaporized as it flows; a refrigeration cycle having the sample table, a compressor, a condenser and an expansion valve connected in that order and having the coolant circulate therein; coolant passages to cause the coolant that has passed through the expansion valve to branch and then merge with a coolant returning from the paths in the sample table toward the compressor; and a regulator to adjust an amount of coolant passing through the paths in the sample table and circulating in the refrigeration cycle and an amount of coolant branching and flowing through the coolant passages.

Plasma processing apparatus capable of adjusting temperature of sample stand

In a plasma processing apparatus equipped with a vacuum vessel and a sample table which is arranged within the vacuum vessel and has a sample mounting plane where a sample is mounted on an upper portion, for forming plasma within the processing chamber so as to process a sample mounted on the sample mounting plane, the plasma processing apparatus includes: a space arranged inside the sample table, into which a coolant is supplied; a ceiling plane of the space arranged opposite to the sample mounting plane, with which the coolant collides from plural portions; and an exhaust port via which the coolant which has collided with the ceiling plane to be evaporated is exhausted from the sample table.

Growing community of inventors

Asaka, Japan

Takumi Tandou